Method of manufacturing semiconductor device, substrate processing apparatus, and recording medium

ABSTRACT

A method of manufacturing a semiconductor device is provided. The method includes treating a surface of an insulating film formed on a substrate by supplying a first gas containing a halogen group to the substrate, and forming a thin film containing a predetermined element on the treated surface of the insulating film by performing a cycle a predetermined number of times. The cycle includes supplying a second gas containing the predetermined element and a halogen group to the substrate, and supplying a third gas to the substrate.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.14/195,444, filed Mar. 3, 2014, which is based upon and claims thebenefit of priority from Japanese Patent Application No. 2013-043539,filed on Mar. 5, 2013, the entire contents of which are incorporatedherein by reference.

TECHNICAL FIELD

The present disclosure relates to a method of manufacturing asemiconductor device including a process of forming a thin film on asubstrate, a substrate processing apparatus, and a recording medium.

BACKGROUND

A process of manufacturing a semiconductor device may include a processof forming a thin film on a substrate by supplying a precursor to thesubstrate.

However, if an insulating film is formed on a surface of a substratethat is a base of film formation, in some cases, step coverage of a thinfilm may decrease, or a discontinuous film having a pinhole (breakpoint)or the like may be formed. In particular, such phenomenon occursremarkably, when a film thickness of a thin film to be formed is set tofall within, for example, a so-called thin film range of 5 Å to 100 Å,or when trenches having a high aspect ratio are formed in a surface ofthe substrate. The use of the discontinuous thin film, for example, in achannel of a transistor device or the like may deteriorate electricalcharacteristics of the device. Furthermore, the use of the discontinuousthin film as an etching stopper of an etching process using hydrogenfluoride (HF) or the like in the manufacturing process of the device maypartially damage a substrate surface of a base, i.e., an insulating filmformed on the substrate surface, resulting in deterioration ofcharacteristics of the device or a production yield.

Furthermore, when an insulating film is formed on the surface of thesubstrate, even if a supply of a precursor to the substrate is started,in some cases, formation of a thin film on the substrate is not easilystarted, resulting in an increase in an incubation time. As a result,the productivity of the device decreases, and the manufacturing costincreases.

SUMMARY

The present disclosure provides some embodiments of a method ofmanufacturing a semiconductor device, a substrate processing apparatusand a recording medium, which improve step coverage of a thin film, andproductivity of the film forming process, when forming the thin film ona substrate having an insulating film formed thereon.

According to one embodiment of the present disclosure, a method ofmanufacturing a semiconductor device, includes: treating a surface of aninsulating film formed on a substrate by supplying a first precursorcontaining a predetermined element and a halogen group to the substrate;and forming a thin film containing the predetermined element on thetreated surface of the insulating film by performing a cycle apredetermined number of times, the cycle comprising: supplying a secondprecursor containing the predetermined element and a halogen group tothe substrate; and supplying a third precursor to the substrate.

According to another embodiment of the present disclosure, a substrateprocessing apparatus, includes: a process chamber configured toaccommodate a substrate; a first precursor supply system configured tosupply a first precursor containing a predetermined element and ahalogen group into the process chamber; a second precursor supply systemconfigured to supply a second precursor containing the predeterminedelement and a halogen group into the process chamber; a third precursorsupply system configured to supply a third precursor into the processchamber; and a control unit configured to control the first precursorsupply system, the second precursor supply system, and the thirdprecursor supply system so as to perform a process of treating a surfaceof an insulating film formed on the substrate by supplying the firstprecursor to the substrate in the process chamber, and a process offorming a thin film containing the predetermined element on the treatedsurface of the insulating film by performing a cycle a predeterminednumber of times, the cycle comprising: supplying the second precursor tothe substrate in the process chamber; and supplying the third precursorto the substrate in the process chamber.

According to still another embodiment of the present disclosure, anon-transitory computer-readable recording medium stores a program thatcauses a computer to perform a process of treating a surface of aninsulating film formed on a substrate by supplying a first precursorcontaining a predetermined element and a halogen group to the substrate;and forming a thin film containing the predetermined element on thetreated surface of the insulating film by performing a cycle apredetermined number of times, the cycle comprising: supplying a secondprecursor containing the predetermined element and a halogen group tothe substrate in the process chamber; and supplying a third precursor tothe substrate in the process chamber.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view illustrating a configuration of a verticalprocessing furnace of a substrate processing apparatus according to someembodiments of the present disclosure, in which a portion of theprocessing furnace is shown in a longitudinal sectional view.

FIG. 2 is a schematic view illustrating a configuration of the verticalprocessing furnace of the substrate processing apparatus according tosome embodiments of the present disclosure, in which a portion of theprocessing furnace is shown in a cross-sectional view taken along a lineA-A in FIG. 1.

FIG. 3 is a schematic view illustrating a configuration of a controllerof the substrate processing apparatus according to some embodiments ofthe present disclosure, in which a control system of the controller isshown by a block diagram.

FIG. 4 is a diagram illustrating a film forming flow in a film formingsequence of an embodiment of the present disclosure.

FIG. 5A is a diagram illustrating a gas supply timing in the filmforming sequence of an embodiment of the present disclosure.

FIG. 5B is a diagram illustrating a gas supply timing in a film formingsequence of another embodiment.

FIG. 6 is a diagram illustrating a gas supply timing in a secondsequence of Modified Example 1 of an embodiment of the presentdisclosure.

FIG. 7 is a diagram illustrating a gas supply timing in a secondsequence of Modified Example 2 of an embodiment of the presentdisclosure.

FIG. 8 is a diagram illustrating a gas supply timing in a secondsequence of Modified Example 3 of an embodiment of the presentdisclosure.

FIG. 9 is a graph illustrating an aspect in which an incubation time isreduced by performing a treatment process.

DETAILED DESCRIPTION First Embodiment of Present Disclosure

Hereinafter, a first embodiment of the present disclosure will bedescribed in detail with reference to the drawings.

(1) Configuration of Substrate Processing Apparatus

FIG. 1 is a schematic view illustrating a configuration of a verticalprocessing furnace of a substrate processing apparatus according to someembodiments, in which a portion of a processing furnace 202 is shown bya longitudinal cross-sectional view. FIG. 2 is a schematic viewillustrating a configuration of the vertical processing furnaceaccording to some embodiments, in which a portion of the processingfurnace 202 is shown by a cross-sectional view taken along a line A-A ofFIG. 1.

As shown in FIG. 1, the processing furnace 202 has a heater 207 as aheating unit (a heating mechanism). The heater 207 has a cylindricalshape and is vertically installed by being supported by a heater base asa support plate (not shown). The heater 207 also functions as anactivation mechanism (an exciting unit) configured to activate (excite)gas by heat, as will be described below.

A reaction tube 203 which constitutes a reaction vessel (a processvessel) is disposed inside the heater 207 in a concentric form along theheater 207. The reaction tube 203 is made of a heat resistant materialsuch as, for example, quartz (SiO₂) or silicon carbide (SiC) and has acylindrical shape with its upper end closed and its lower end opened. Aprocess chamber 201 is formed in a hollow cylindrical portion of thereaction tube 203 and is configured to accommodate wafers 200 assubstrates. The wafers 200 are horizontally stacked in multiple stagesto be aligned in a vertical direction in a boat 217 which will bedescribed below.

A first nozzle 249 a, a second nozzle 249 b, and a third nozzle 249 care installed in the process chamber 201 so as to penetrate a lowerportion of the reaction tube 203. A first gas supply pipe 232 a, asecond gas supply pipe 232 b, and a third gas supply pipe 232 c areconnected to the first nozzle 249 a, the second nozzle 249 b, and thethird nozzle 249 c, respectively. Furthermore, a fourth gas supply pipe232 d is connected to the third gas supply pipe 232 c. In this way, thethree nozzles 249 a to 249 c and the four gas supply pipes 232 a to 232d are provided in the reaction tube 203 to allow several kinds (fourkinds in this example) of gases to be supplied into the process chamber201.

Furthermore, a manifold (not shown) made of metal which supports thereaction tube 203 may be installed below the reaction tube 203, and eachnozzle may be installed to penetrate a side wall of the metallicmanifold. In this case, an exhaust pipe 231 to be described below may befurther installed in the metallic manifold. Further, the exhaust pipe231 may be installed at a lower portion of the reaction tube 203 ratherthan at the metallic manifold. In this way, a furnace opening portion ofthe processing furnace 202 may be made of metal and the nozzle or thelike may be mounted on the metallic furnace opening portion.

A mass flow rate controller (MFC) 241 a serving as a flow ratecontroller (a flow control unit) and a valve 243 a serving as anopening/closing valve are installed in the first gas supply pipe 232 asequentially from an upstream direction. Furthermore, a first inert gassupply pipe 232 e is connected to the first gas supply pipe 232 a at adownstream side of the valve 243 a. An MFC 241 e serving as a flow ratecontroller (a flow rate control unit) and a valve 243 e serving as anopening/closing valve are installed in the first inert gas supply pipe232 e sequentially from an upstream direction. Furthermore, theabove-described first nozzle 249 a is connected to a front end of thefirst gas supply pipe 232 a. The first nozzle 249 a is installed in anarc-shaped space between an inner wall of the reaction tube 203 and thewafers 200. The first nozzle 249 a is vertically disposed along theinner wall of the reaction tube 203 to rise upward in a stackingdirection of the wafers 200. That is, the first nozzle 249 a isinstalled in a flank of a wafer arrangement region where the wafers 200are arranged. The first nozzle 249 a is configured as an L-shaped longnozzle, a horizontal portion thereof is installed to penetrate a lowersidewall of the reaction tube 203, and a vertical portion thereof isinstalled to rise from one end to the other end of the wafer arrangementregion. A plurality of gas supply holes 250 a through which gas issupplied is formed at a side surface of the first nozzle 249 a. The gassupply holes 250 a are opened toward a center of the reaction tube 203so that gas can be supplied toward the wafer 200. The gas supply holes250 a are disposed at a predetermined opening pitch from a lower portionto an upper portion of the reaction tube 203. The plurality of gassupply holes 250 a has the same opening area.

A first gas supply system is mainly configured by the first gas supplypipe 232 a, the MFC 241 a, and the valve 243 a. Also, the first nozzle249 a may be considered to be included in the first gas supply system.Furthermore, a first inert gas supply system is mainly configured by thefirst inert gas supply pipe 232 e, the MFC 241 e, and the valve 243 e.The first inert gas supply system also functions as a purge gas supplysystem.

An MFC 241 b serving as a flow rate controller (a flow rate controlunit) and a valve 243 b serving as an opening/closing valve areinstalled in the second gas supply pipe 232 b sequentially from anupstream direction. Furthermore, a second inert gas supply pipe 232 f isconnected to the second gas supply pipe 232 b at a downstream side ofthe valve 243 b. An MFC 241 f serving as a flow rate controller (a flowrate control unit) and a valve 243 f serving as an opening/closing valveare installed in the second inert gas supply pipe 232 f sequentiallyfrom an upstream direction. Furthermore, the above-described secondnozzle 249 b is connected to a front end of the second gas supply pipe232 b. The second nozzle 249 b is installed in an arc-shaped spacebetween the inner wall of the reaction tube 203 and the wafers 200. Thesecond nozzle 249 b is vertically disposed along the inner wall of thereaction tube 203 to rise upward in the stacking direction of the wafers200. That is, the second nozzle 249 b is installed in the flank of thewafer arrangement region where the wafers 200 are arranged. The secondnozzle 249 b is configured as an L-shaped long nozzle, a horizontalportion thereof is installed to penetrate a lower sidewall of thereaction tube 203, and a vertical portion thereof is installed to risefrom one end to the other end of the wafer arrangement region. Aplurality of gas supply holes 250 b through which gas is supplied isformed at a side surface of the second nozzle 249 b. The gas supplyholes 250 b are opened toward a center of the reaction tube 203 so thatgas can be supplied toward the wafer 200. The gas supply holes 250 b aredisposed at a predetermined opening pitch from the lower portion to theupper portion of the reaction tube 203. The plurality of gas supplyholes 250 b has the same opening area.

A second gas supply system is mainly configured by the second gas supplypipe 232 b, the MFC 241 b, and the valve 243 b. Also, the second nozzle249 b may be considered to be included in the second gas supply system.Furthermore, the second inert gas supply system is mainly configured bythe second inert gas supply pipe 232 f, the MFC 241 f, and the valve 243f. The second inert gas supply system also functions as a purge gassupply system.

An MFC 241 c serving as a flow rate controller (a flow rate controlunit) and a valve 243 c serving as an opening/closing valve areinstalled in the third gas supply pipe 232 c sequentially from anupstream direction. Furthermore, a fourth gas supply pipe 232 d isconnected to the third gas supply pipe 232 c at a downstream side of thevalve 243 c. An MFC 241 d serving as a flow rate controller (a flow ratecontrol unit) and a valve 243 d serving as an opening/closing valve areinstalled in the fourth gas supply pipe 232 d sequentially from anupstream direction. Moreover, a third inert gas supply pipe 232 g isconnected to the third gas supply pipe 232 c at a downstream side of aconnection position between the third gas supply pipe 232 c and thefourth gas supply pipe 232 d. An MFC 241 g serving as a flow ratecontroller (a flow rate control unit) and a valve 243 g serving as anopening/closing valve are installed in the third inert gas supply pipe232 g sequentially from an upstream direction. Furthermore, theabove-described third nozzle 249 c is connected to a front end of thethird gas supply pipe 232 c. The third nozzle 249 c is installed in anarc-shaped space between the inner wall of the reaction tube 203 and thewafers 200. The third nozzle 249 c is vertically disposed along theinner wall of the reaction tube 203 to rise upward in the stackingdirection of the wafers 200. That is, the third nozzle 249 c isinstalled in the flank of the wafer arrangement region where the wafers200 are arranged. The third nozzle 249 c is configured as an L-shapedlong nozzle, a horizontal portion thereof is installed to penetrate alower sidewall of the reaction tube 203, and a vertical portion thereofis installed to rise from one end to the other end of the waferarrangement region. A plurality of gas supply holes 250 c through whichgas is supplied is formed on a side surface of the third nozzle 249 c.The gas supply holes 250 c are opened toward a center of the reactiontube 203 so that gas can be supplied toward the wafer 200. The gassupply holes 250 c are disposed at a predetermined opening pitch fromthe lower portion to the upper portion of the reaction tube 203. Theopenings of each of the plurality of gas supply holes 250 c, each havethe same opening area.

A third gas supply system is mainly configured by the third gas supplypipe 232 c, the MFC 241 c, and the valve 243 c. Also, the third nozzle249 c may be considered to be included in the third gas supply system.Furthermore, a fourth gas supply system is mainly configured by thefourth gas supply pipe 232 d, the MFC 241 d, and the valve 243 d.Moreover, the third nozzle 249 c may be considered to be included in thefourth gas supply system at a downstream side of a connection positionwith the fourth gas supply pipe 232 d in the third gas supply pipe 232c. Moreover, a third inert gas supply system is mainly configured by athird inert gas supply pipe 232 g, an MFC 241 g, and a valve 243 g. Thethird inert gas supply system also functions as a purge gas supplysystem.

Thus, in the method of supplying the gas in this embodiment, the gasesare transferred via the nozzles 249 a to 249 c disposed in an elongatedarc-shaped space defined between the inner wall of the reaction tube 203and the end portion of the plurality of stacked wafers 200, and thegases are first ejected into the reaction tube 203 in the vicinity ofthe wafer 200 from the gas supply holes 250 a to 250 c which areopenings in the nozzles 249 a to 249 c, respectively. Thus, the mainflow paths of the gases in the reaction tube 203 are set in a directionparallel to the surfaces of the wafers 200, that is, in a horizontaldirection. With such a configuration, the gas can be uniformly suppliedto each wafer 200, thereby obtaining an effect of making a filmthickness of a thin film formed on each wafer 200 uniform. The gasflowing over the surface of the wafer 200, that is, the residual gasafter reaction, flows in the direction of an exhaust pipe 231 to bedescribed later, but the direction of the flow of the residual gas isappropriately specified depending on a position of the exhaust port, andis not limited to a vertical direction.

From the first gas supply pipe 232 a, as a first precursor containing apredetermined element and a halogen group and a second precursorcontaining a predetermined element and a halogen group, for example, achlorosilane-based precursor gas containing at least silicon (Si) and achloro group, is supplied into the process chamber 201 via the MFC 241a, the valve 243 a, and the first nozzle 249 a. Here, thechlorosilane-based precursor gas is a chlorosilane-based precursor in agaseous state, for example, a gas obtained by vaporizing thechlorosilane-based precursor in a liquid state under normal temperatureand pressure, a chlorosilane-based precursor in a gaseous state undernormal temperature and pressure or the like. Further, thechlorosilane-based precursor is a silane-based precursor having a chlorogroup as a halogen group, and is a precursor containing at least Si andCl. In other words, the chlorosilane-based precursor used herein mayrefer to a kind of halide. In the case of using the term “precursor”herein, it may refer to a “liquid precursor in a liquid state”,“precursor gas in a gaseous state” or both of them. Therefore, in thecase of using the term “chlorosilane-based precursor” as used herein, itmay refer to a “chlorosilane-based precursor in a liquid state”, a“chlorosilane-based precursor gas in a gaseous state”, or both of them.As the chlorosilane-based precursor, for example, hexachlorodisilane(Si₂Cl₆, abbreviation: HCDS) can be used. Furthermore, in the case ofusing a liquid precursor such as HCDS which is in a liquid state undernormal temperature and pressure, the liquid precursor may be vaporizedby a vaporization system such as a vaporizer or a bubbler to be suppliedas a precursor gas (HCDS gas).

From the second gas supply pipe 232 b, as a third precursor containing apredetermined element and an amino group (amine group), for example, aaminosilane-based precursor gas containing at least Si and an aminogroup, is supplied into the process chamber 201 via the MFC 241 b, thevalve 243 b, and the second nozzle 249 b. Here, the aminosilane-basedprecursor gas is an aminosilane-based precursor in a gaseous state, forexample, a gas obtained by vaporizing the aminosilane-based precursor ina liquid state under normal temperature and pressure, anaminosilane-based precursor in a gaseous state under normal temperatureand pressure or the like. Further, the aminosilane-based precursor is asilane-based precursor having an amino group (also a silane-basedprecursor also containing an alkyl group such as a methyl group, anethyl group or a butyl group), and is a silane-based precursorcontaining at least Si, carbon (C), and nitrogen (N). That is, theaminosilane-based precursor used herein may also be referred to as anorganic precursor, and an organic aminosilane-based precursor.Furthermore, when using the term “the aminosilane-based precursor”herein, it may refer to an “aminosilane-based precursor in a liquidstate”, “aminosilane-based precursor gas in a gaseous state” or both ofthem. As the aminosilane-based precursor, it is possible to use, forexample, monoaminosilane (SiH₃R) which is a precursor containing oneamino group in the composition formula (one molecule). Here, Rrepresents a ligand, and in this case, R represents an amino group inwhich one or two hydrocarbon groups including one or more C atoms is/arecoordinated in one N atom (one or both of H of an amino grouprepresented by NH₂ is/are substituted with a hydrocarbon group includingone or more C atoms). When two hydrocarbon groups constituting a part ofthe amino group are coordinated in one N, both of them may be the samehydrocarbon group, or may be different hydrocarbon groups from eachother. Further, the hydrocarbon group may include an unsaturated bondsuch as a double bond or a triple bond. Further, the amino group mayhave a cyclic structure. For example, as SiH₃R, it is possible to use(ethylmethylamino) silane (SiH₃[N(CH₃)(C₂H₅)]), (dimethylamino) silane(SiH₃[N(CH₃)₂]), (diethylpiperidino) silane (SiH₃[NC₅H₈(C₂H₅)₂]) or thelike. Furthermore, when using a liquid precursor such as SiH₃R which isin a liquid state under normal temperature and pressure, the liquidprecursor may be vaporized by a vaporization system such as a vaporizeror a bubbler to be supplied as a precursor gas (SiH₃R gas).

From the third gas supply pipe 232 c, as a fourth precursor containing apredetermined element, for example, a silane-based precursor gascontaining Si and containing no Cl, C, N, and oxygen (O), that is, aninorganic silane-based precursor gas is supplied into the processchamber 201 via the MFC241 c, the valve 243 c, the third nozzle 249 c.In this case, the inorganic silane-based precursor gas may also bereferred to as a silane-based precursor gas containing no Cl, C, N, andO. As a silane-based precursor gas (inorganic silane-based precursorgas), for example, a monosilane (SiH₄) gas can be used.

From the fourth gas supply pipe 232 d, as a fifth precursor containing apredetermined elemental and an amino groups (amine group), for example,an aminosilane-based precursor gas containing at least Si and an aminogroup, is supplied into the process chamber 201 via the MFC 241 d, thevalve 243 d, the third gas supply pipe 232 c, and the third nozzle 249c. As an aminosilane-based precursor gas, for example, it is possible touse a trisdimethylaminosilane (Si[N(CH₃)₂]₃H, abbreviation: 3DMAS) gasthat is a precursor containing a plurality of amino groups in thecomposition formula (in one molecule). When using a liquid precursorthat is in a liquid state under room temperature and atmosphericpressure, such as 3DMAS, the liquid precursor is vaporized by avaporization system such as a vaporizer or a bubbler to be supplied as aprecursor gas as (3DMAS gas).

From the inert gas supply pipes 232 e to 232 g, as an inert gas, forexample, a nitrogen (N₂) gas is supplied into the process chamber 201via the MFCs 241 e to 241 g, the valves 243 e to 243 g, the gas supplypipes 232 a to 232 c, and the nozzles 249 a to 249 c, respectively.

When allowing the gases as described above to flow from each gas supplypipe, respectively, a first precursor supply system configured to supplya first precursor containing a predetermined element and a halogengroup, that is, a chlorosilane-based precursor gas supply system as afirst precursor gas supply system, is configured by the first gas supplysystem. Furthermore, a second precursor supply system configured tosupply a second precursor containing a predetermined element and ahalogen group, that is, a chlorosilane-based precursor gas supply systemas a second precursor gas supply system, is configured by the first gassupply system. Moreover, the chlorosilane-based precursor gas supplysystem is also simply referred to as a chlorosilane-based precursorsupply system. Furthermore, a third precursor supply system configuredto supply a third precursor containing a predetermined element and anamino group, that is, an aminosilane-based precursor gas supply systemas a third precursor gas supply system, is configured by the second gassupply system. Moreover, the aminosilane-based precursor gas supplysystem is also simply referred to as an aminosilane-based precursorsupply system. Furthermore, a fourth precursor supply system configuredto supply a fourth precursor containing a predetermined element, thatis, a silane-based precursor gas supply system (inorganic silane-basedprecursor gas supply system) as a fourth precursor gas supply system, isconfigured by the third gas supply system. Moreover, the silane-basedprecursor gas supply system (inorganic silane-based precursor gas supplysystem) is also simply referred to as a silane-based precursor supplysystem (inorganic silane-based precursor supply system). Furthermore, afifth precursor supply system configured to supply a fifth precursorcontaining a predetermined element and an amino group, that is, anaminosilane-based precursor gas supply system as a fifth precursor gassupply system, is configured by the fourth gas supply system. Moreover,the aminosilane-based precursor gas supply system is also simplyreferred to as an aminosilane-based precursor supply system.

The exhaust pipe 231 configured to exhaust an internal atmosphere in theprocess chamber 201 is installed in the reaction tube 203. As shown inFIG. 2, when seen from a horizontal cross-sectional view, the exhaustpipe 231 is installed at a side opposite to a side of the reaction tube203 in which the gas supply holes 250 a of the first nozzle 249 a, thegas supply hole 250 b of the second nozzle 249 b, and the gas supplyhole 250 c of the third nozzle 249 c are formed, that is, at a sideopposite to the gas supply holes 250 a to 250 c with the wafer 200interposed therebetween. Further, in a longitudinal cross-sectional viewas shown in FIG. 1, the exhaust pipe 231 is provided below a positionwhere the gas supply holes 250 a to 250 c are formed. With such aconfiguration, the gas supplied to the vicinity of the wafers 200 in theprocess chamber 201 through the gas supply holes 250 a to 250 c flows ina horizontal direction, i.e., in a direction parallel to the surfaces ofthe wafers 200, and then flows downward and is exhausted from theexhaust pipe 231. As described above, the main flow of the gas in theprocess chamber 201 is directed in the horizontal direction.

A vacuum pump 246 as a vacuum exhaust device is connected to the exhaustpipe 231 via a pressure sensor 245 as a pressure detector (pressuredetecting unit) configured to detect the internal pressure of theprocess chamber 201, and an auto pressure controller (APC) valve 244 asa pressure adjuster (pressure adjusting unit). Furthermore, the APCvalve 244 is configured to be able to perform and stop thevacuum-exhaust of the process chamber 201 by opening and closing thevalve in the state of operating the vacuum pump 246, and to adjust theinternal pressure of the process chamber 201 by adjusting a degree ofvalve opening in the state of operating the vacuum pump 246. An exhaustsystem is mainly configured by the exhaust pipe 231, the APC valve 244,and the pressure sensor 245. Furthermore, the vacuum pump 246 may beconsidered to be included in the exhaust system. The exhaust system isconfigured to be able to perform the vacuum-exhaust such that theinternal pressure of the process chamber 201 becomes a predeterminedpressure (vacuum level), by adjusting the degree of valve opening of theAPC valve 244 on the basis of the pressure information detected by thepressure sensor 245, while operating the vacuum pump 246.

A seal cap 219, which functions as a furnace port cover capable ofhermetically sealing a lower end opening of the reaction tube 203, isinstalled below the reaction tube 203. The seal cap 219 is configured tocome into contact with the lower end portion of the reaction tube 203from the downside in the vertical direction. The seal cap 219 is madeof, for example, a metal such as stainless steel, and is formed in adisc shape. An O-ring 220, which is a seal member in contact with thelower end portion of the reaction tube 203, is installed on the uppersurface of the seal cap 219. On a side of the seal cap 219 opposite tothe process chamber 201, a rotation mechanism 267 as a substrate holderto be described later configured to rotate a boat 217 is installed. Arotary shaft 255 of the rotation mechanism 267 is connected to the boat217 through the seal cap 219. The rotation mechanism 267 is configuredto rotate the wafers 200 by rotating the boat 217. The seal cap 219 isconfigured to be vertically raised and lowered by a boat elevator 115 asan elevating mechanism vertically installed at the outside of thereaction tube 203. The boat elevator 115 is configured to be able toload and unload the boat 217 into and from the process chamber 201 byraising and lowering the seal cap 219. In other words, the boat elevator115 is configured as a transfer device (a transfer mechanism) thattransfers the boat 217, that is, the wafers 200 into and out of theprocess chamber 201.

The boat 217, which is used as a substrate support device, is made of,for example, a heat resistant material such as quartz or siliconcarbide, and is configured to support a plurality of wafers 200horizontally stacked in multiple stages with the centers of the wafers200 concentrically aligned. A heat insulating member 218, for example,made of a heat resistant material, such as quartz and silicon carbide,is installed at the lower portion of the boat 217 and configured suchthat heat from the heater 207 is not easily transmitted to the seal cap219. In addition, the heat insulating member 218 may be configured by aplurality of heat insulating plates made of a heat resistant materialsuch as quartz or silicon carbide, and a heat insulating plate holderconfigured to support these heat insulating plates at a horizontalposition in multiple stages.

A temperature sensor 263, which is a temperature detector, is installedin the reaction tube 203 such that the interior of the process chamber201 reaches a desired temperature distribution by adjusting an electricconduction state to the heater 207 based on the temperature informationdetected by the temperature sensor 263. The temperature sensor 263 isconfigured in an L shape similarly to the nozzles 249 a, 249 b, and 249c and installed along the inner wall of the reaction tube 203.

As shown in FIG. 3, a controller 121 serving as a control part (controlunit) is configured as a computer that is equipped with a centralprocessing unit (CPU) 121 a, a random access memory (RAM) 121 b, astorage device 121 c, and an I/O port 121 d. The RAM 121 b, the storagedevice 121 c, and the I/O port 121 d are configured to be able toexchange data with the CPU 121 a via an internal bus 121 e. Aninput/output device 122 including, for example, a touch panel or thelike, is connected to the controller 121.

The storage device 121 c is configured by, for example, a flash memory,a hard disk drive (HDD) or the like. A control program for controllingthe operation of the substrate processing apparatus or a process recipe,in which a procedure, condition of processing the substrate and the likedescribed later are written, is readably stored in the storage device121 c. Furthermore, the process recipe functions as a program to causethe controller 121 to execute each procedure in a substrate processingprocess described later to obtain a predetermined result. Hereinafter,the process recipe, the control program and the like may be generallysimply referred to as a program. When using the term “program” herein,it may indicate a case of including only a process recipe, a case ofincluding only a control program, or a case of using both of them. Inaddition, the RAM 121 b is configured as a memory region (work area) inwhich the program, the data or the like read by the CPU 121 a istemporarily stored.

The I/O port 121 d is connected to the MFC 241 a to 241 g, the valves243 a to 243 g, the pressure sensor 245, the APC valve 244, the vacuumpump 246, the heater 207, the temperature sensor 263, the rotationmechanism 267, the boat elevator 115 and the like.

The CPU 121 a is configured to read and execute the control program fromthe storage device 121 c and to read the process recipe from the storagedevice 121 c in accordance with an input of an operation command or thelike from the input/output device 122. Moreover, the CPU 121 a isconfigured to control the flow rate adjusting operation of various gasesusing the MFC 241 a to 241 g, the opening and closing operation of thevalves 243 a to 243 g, the opening and closing operation of the APCvalve 244, and the pressure adjusting operation of the APC valve 244based on the pressure sensor 245, the temperature adjusting operation ofthe heater 207 based on the temperature sensor 263, the start-up andstop operation of the vacuum pump 246, the rotation and the rotationspeed adjusting operation of the boat 217 by the rotation mechanism 267,the elevation operation of the boat 217 by the boat elevator 115 or thelike, according to the contents of the process recipe that has beenread.

Furthermore, the controller 121 is not limited to a case of beingconfigured as a dedicated computer but may be configured as ageneral-purpose computer. For example, it is possible to configure thecontroller 121 according to this embodiment, by preparing an externalstorage device 123 that stores the above-described program (for example,a magnetic tape, a magnetic disk such as a flexible disk or a hard disk,an optical disk such as a CD or a DVD, a magneto-optical disk such as anMO, and a semiconductor memory such as a USB memory or a memory card),and installing the program on the general-purpose computer using theexternal storage device 123. Furthermore, a means for supplying aprogram to a computer is not limited to a case in which the program issupplied via the external storage device 123. For example, the programmay be supplied by the use of communication means such as the Internetor a dedicated line, rather than using the external storage device 123.The storage device 121 c or the external storage device 123 isconfigured as a non-transitory computer-readable recording medium.Hereinafter, these are collectively and simply referred to as a“recording medium”. In the case of using the term “recording medium”herein, it may include a case of including only the storage device 121c, a case of including only the external storage device 123 alone, or acase of including both of them.

(2) Substrate Processing Process

Next, a sequence example of performing treatment on a surface of aninsulating film formed on a surface of a substrate and then forming athin film containing a predetermined element on a surface of a treatedinsulating film, as one process of manufacturing processes of asemiconductor device (device), using the processing furnace 202 of theabove-described substrate processing apparatus will be described withreference to FIGS. 4 and 5A. FIG. 4 is a flow chart illustrating a filmforming flow of a film forming sequence, according to some embodiments|.FIG. 5A is a gas supply timing diagram in the film forming sequence,according to some embodiments. In the following description, operationsof each part constituting the substrate processing apparatus arecontrolled by the controller 121.

In a film forming sequence of the embodiment, the following processesare performed:

performing treatment on a surface of an insulating film formed on asubstrate by supplying a first precursor containing a predeterminedelement and a halogen group to the substrate with the insulating filmformed thereon; and forming a thin film containing the predeterminedelement on the surface of the treated insulating film by performing acycle a predetermined number of times, the cycle including: supplying asecond precursor containing the predetermined element and a halogengroup to the substrate; and supplying a third precursor to thesubstrate.

Here, the expression “performing a cycle including supplying a secondprecursor and supplying a third precursor a predetermined number oftimes” includes a case of performing the cycle once, and a case ofrepeating this cycle multiple times. In other words, it means that thecycle is performed one or more times (a predetermined number of times).

Hereinafter, the film forming sequence of the embodiment will bespecifically described. Here, an example, in which a silicon film (Sifilm) composed of Si is formed on a surface of a silicon oxide film(SiO₂ film, hereinafter, also referred to as an SiO film) serving as aninsulating film formed on the surface of the wafer 200, using an HCDSgas which is a chlorosilane-based precursor gas as the first precursorand the second precursor, and using an SiH₃R gas which is anaminosilane-based precursor gas as the third precursor, by the filmforming flow of FIG. 4 and the film forming sequence of FIG. 5A, will bedescribed. Furthermore, the SiO film becomes a part of a base film whenforming an Si film in an Si film forming process which will be describedlater.

Moreover, when the term “wafer” is used herein, it may refer to “thewafer itself” or “the wafer and a laminated body (a collected body) ofpredetermined layers or films formed on a surface thereof” (i.e., thewafer including the predetermined layers or films formed on the surfacemay be referred to as a wafer). In addition, the phrase “a surface of awafer” as used herein may refer to “a surface (an exposed surface) of awafer itself” or “a surface of a predetermined layer or film formed onthe wafer, i.e., the uppermost surface of the wafer as a laminatedbody.”

Therefore, the expression “supplying a predetermined gas to a wafer”herein may mean that “a predetermined gas is directly supplied to asurface (exposed surface) of a wafer itself” or that “a predeterminedgas is supplied to a layer or a film formed on a wafer, i.e., to anuppermost surface of a wafer as a laminated body.” In addition, theexpression “a predetermined layer (or film) is formed on a wafer” maymean that “a predetermined layer (or film) is directly formed on asurface (an exposed surface) of” a wafer itself′ or that “apredetermined layer (or film) is formed on a layer or a film formed on awafer, i.e., on an uppermost surface of a wafer as a laminated body.”

Moreover, the term “substrate” as used herein may be synonymous with theterm “wafer,” and in this case, the terms “wafer” and “substrate” may beused interchangeably in the above description.

(Wafer Charging and Boat Loading)

When a plurality of wafers 200 is charged on the boat 217 (wafercharging), as shown in FIG. 1, the boat 217 supporting the plurality ofwafers 200 is raised by the boat elevator 115 and loaded into theprocess chamber 201 (boat loading). In this state, the seal cap 219seals the lower end of the reaction tube 203 via the O-ring 220.

(Pressure Adjustment and Temperature Adjustment)

The interior of the process chamber 201, that is, a space in which thewafers 200 are present is vacuum evacuated by the vacuum pump 246 suchthat the interior of the process chamber 201 reaches a desired pressure(vacuum level). At this time, the internal pressure of the processchamber 201 is measured by the pressure sensor 245, and the APC valve244 is feedback-controlled based on the measured pressure information(pressure adjustment). Furthermore, the vacuum pump 246 maintains aregular operation state at least until processing of the wafers 200 isterminated. Furthermore, the interior of the process chamber 201 isheated by the heater 207 to a desired temperature. At this time, anelectrical conduction state to the heater 207 is feedback-controlledbased on the temperature information detected by the temperature sensor263 such that the interior of the process chamber 201 reaches a desiredtemperature distribution (temperature adjustment). In addition, heatingof the interior of the process chamber 201 by the heater 207 iscontinuously performed at least until processing of the wafers 200 isterminated. Next, the boat 217 and the wafers 200 begin to be rotated bythe rotation mechanism 267. Furthermore, the rotation of the boat 217and the wafers 200 by the rotation mechanism 267 is continuouslyperformed at least until processing on the wafers 200 is terminated.

(Treatment Process)

Thereafter, a treatment process (pre-process) is performed on thesurface of the SiO film formed on the surface of the wafer 200. In thisprocess, a seed layer containing Cl as a halogen group and Si as apredetermined element is formed on the surface of the SiO film, as aninitial layer.

The valve 243 a of the first gas supply pipe 232 a is opened to flow theHCDS gas into the first gas supply pipe 232 a. A flow rate of the HCDSgas flowing into the first gas supply pipe 232 a is adjusted by the MFC241 a. The flow rate-adjusted HCDS gas is supplied into the processchamber 201 from the gas supply holes 250 a of the first nozzle 249 a,and exhausted from the exhaust pipe 231. At this time, the HCDS gas issupplied to the wafer 200. At the same time, the valve 243 e is openedto flow an inert gas such as an N₂ gas into the first inert gas supplypipe 232 e. A flow rate of the N₂ gas flowing through the first inertgas supply pipe 232 e is adjusted by the MFC 241 e. The flowrate-adjusted N₂ gas is supplied into the process chamber 201 togetherwith the HCDS gas, and exhausted from the exhaust pipe 231.

Furthermore, at this time, in order to prevent the infiltration of theHCDS gas into the second nozzle 249 b and the third nozzle 249 c, thevalves 243 f and 243 g are opened to flow the N₂ gas into the secondinert gas supply pipe 232 f and the third inert gas supply pipe 232 g.The N₂ gas is supplied into the process chamber 201 through the secondgas supply pipe 232 b, the third gas supply pipe 232 c, the secondnozzle 249 b, and the third nozzle 249 c, and exhausted from the exhaustpipe 231.

At this time, the APC valve 244 is appropriately adjusted to set theinternal pressure of the process chamber 201 to fall within a range of,for example, 1 to 13300 Pa, or more specifically, 20 to 1330 Pa.Furthermore, a supply flow rate of the HCDS gas controlled by the MFC241 a is set to fall within a range of, for example, 1 to 1000 sccm. Asupply flow rate of the N₂ gas controlled by the MFCs 241 e to 241 g isset to fall within a range of, for example, 100 to 10000 sccm.

Furthermore, at this time, if the supply flow rate of the HCDS gas isset to be greater than the supply flow rate of the HCDS gas in an Sifilm forming process to be described later, or the internal pressure ofthe process chamber 201 is set to be greater than the internal pressureof the process chamber 201 when supplying the HCDS gas in the Si filmforming process to be described later, it is possible to increase aforming rate of a seed layer on the surface of the SiO film, therebyimproving the total productivity in the film forming process. Also, theseed layer is easily formed in a continuous layer, and as a result, itis possible to improve flatness of the Si film formed in the Si filmforming process to be described later, that is, a uniformity of a filmthickness in a plane of the wafer 200. Further, it is also possible toimprove step coverage of the Si film.

Furthermore, a time of supplying the HCDS gas to the wafer 200, i.e., agas supply time (irradiation time) of the HCDS gas, is set to be longerthan a gas supply time of the HCDS gas per cycle in the Si film formingprocess to be described later. Specifically, the gas supply time of theHCDS gas is set to fall within a range of, for example, 120 seconds ormore to 1200 seconds or less, more specifically, 300 seconds or more to900 seconds or less, or further more specifically, 600 seconds or moreto 900 seconds or less.

When the gas supply time is less than 120 seconds, a thickness of a seedlayer formed on the surface of the SiO film becomes too thin (forexample, becomes a thickness of less than 0.5 Å), and the seed layerbecomes a discontinuous layer. In this case, since the Si film formingprocess to be described later is performed in a state in which the SiOfilm is partially exposed, a uniformity of a film thickness of an Sifilm to be formed in a plane of the wafer 200 is likely to decrease, andthe step coverage is likely to decrease. If the gas supply time is setto 120 seconds or more, the seed layer can be continuously formed, thatis, the seed layer can become a continuous layer. Furthermore, if thegas supply time is set to 300 seconds (5 minutes) or more, or morespecifically 600 seconds (10 minutes) or more, it becomes easier toprovide a continuous seed layer. As a result, even if the film thicknessof the Si film is set to fall within a so-called thin film range, forexample, 5 Å to 100 Å, or more specifically, 20 Å to 100 Å, it ispossible to provide a continuous Si film having no pinholes. Further, itis also possible to increase the flatness of the Si film surface, i.e.,to improve the uniformity of the film thickness of the Si film in aplane of the wafer 200. Further, it is also possible to improve the stepcoverage of the Si film.

Further, when the gas supply time exceeds 1800 seconds (30 minutes), athickness of the seed layer formed on the surface of the SiO filmbecomes too thick (becomes a thickness of, for example, more than 2 Å).Thus, when a laminated film of the seed layer formed on the SiO film andthe Si film is considered in total, an impurity concentration of Cl orthe like in the film (in particular, a lower layer) may increase,resulting in a change of film quality. Further, total consumption of theHCDS gas in the treatment process increases, resulting in an increase offilm forming costs. As the gas supply time is set to 1800 seconds orless, such problems can be solved. In particular, as the gas supply timeis set to 1200 seconds (20 minutes) or more, or 900 seconds (15 minutes)or less, the total film quality of the laminated film of the seed layerand the Si film formed on the SiO film may become a more appropriatefilm quality. Further, it is possible to more appropriately suppress theamount of waste of the HCDS gas in the treatment process, therebyfurther reducing the film forming costs.

Furthermore, a temperature of the wafer 200 is set to fall within arange of, for example, 250 to 700 degrees C., more specifically, 300 to650 degrees C., or further more specifically, 350 to 650 degrees C.

When the temperature of the wafer 200 is less than 250 degrees C., theseed layer is hardly formed on the surface of the SiO film, resulting ina failure to obtain a forming rate of a practical seed layer. Thisproblem can be solved by setting the temperature of the wafer 200 to 250degrees C. or more. Also, by setting the temperature of the wafer 200 to300 degrees C. or more or 350 degrees C. or more, the seed layer can bemore sufficiently formed on the surface of the SiO film, thereby furtherincreasing the forming rate of the seed layer.

Furthermore, when the temperature of the wafer 200 exceeds 700 degreesC., since a CVD reaction is strengthened (a gaseous reaction becomesdominant), a uniformity of a thickness of the seed layer in a plane ofthe wafer 200 may easily deteriorate making it difficult to control theuniformity. By setting the temperature of the wafer 200 to 700 degreesC. or less, deterioration of the uniformity of the thickness of the seedlayer in a plane of the wafer 200 can be suppressed, and thus, it ispossible to control the uniformity. In particular, a surface reactionbecomes dominant by setting the temperature of the wafer 200 to 650degrees C. or less or 600 degrees C., the uniformity of the thickness ofthe seed layer in a plane of the wafer 200 can be easily secured, andthus, it becomes easy to control the uniformity.

In this way, when the temperature of the wafer 200 is set to fall withina range of, for example, 250 to 700 degrees C., more specifically 300 to650 degrees C., or further more specifically, 350 to 600 degrees C., itis possible to allow the treatment process, i.e., the formation of theseed layer on the surface of the SiO film to progress.

However, although the details will be described later, when thetemperature of the wafer 200 is less than 300 degrees C., it is hard fora modification reaction (modification reaction of the first layer) inStep 2 of the Si film forming process to be described later to progress.By setting the temperature of the wafer 200 to 300 degrees C. or more,it is possible to facilitate the progress of the modification reactionin Step 2. Further, by setting the temperature of the wafer 200 to 350degrees C. or more, the modification reaction in Step 2 becomes moreactive. In addition, when the temperature of the wafer 200 exceeds 450degrees C., it is difficult to allow the modification reaction in Step 2to appropriately progress. That is, in order to allow the process inStep 2 of the Si film forming process to be described later toefficiently and appropriately progress, the temperature of the wafer 200may be set in the range of, for example, 300 to 450 degrees C., or morespecifically, 350 to 450 degrees C.

In this way, appropriate temperature conditions differ between thetreatment process and Step 2 of the Si film forming process to bedescribed later, and a temperature range suitable for allowing Step 2 ofthe Si film forming process to be described later to progress may beincluded in a temperature range suitable for allowing the treatmentprocess to progress. Here, as in this embodiment, when the treatmentstep and the Si film forming process are continuously performed in thesame process chamber 201, in order to improve the total throughput, thetemperature of the wafer 200 may be set to have the same temperatureconditions in the treatment process and the Si film forming process tobe described later. That is, the temperature conditions of the wafer 200in the treatment process may be set to be equal to the temperatureconditions of the wafer 200 in the Si film forming process to bedescribed later. Therefore, in the treatment process, the temperature ofthe wafer 200 may be set to fall within a range of, for example, 300 to450 degrees C., or more specifically, 350 to 450 degrees C. Within thistemperature range, it is possible to allow the process (formation of theseed layer) in the treatment process and the processes (formation of thefirst layer, and modification of the first layer) in Steps 1 and 2 ofthe Si film forming process to be described later to efficiently andappropriately progress, respectively.

By supplying the HCDS gas to the wafer 200 under the above-describedconditions, as a seed layer having a thickness of, for example, 0.5 to 2Å, a layer containing Cl as a halogen group, and more specifically, alayer containing Cl as a halogen group and Si as a predetermined elementis formed on the SiO film on the surface of the wafer 200. The seedlayer becomes a continuous and flat layer throughout the entire areas inthe surface of the wafer 200, as described above. Furthermore, thesurface of the seed layer becomes a surface terminated by an Si—Cl bond(hereinafter, also simply referred to as Cl termination). By the Cltermination, the surface of the seed layer becomes a surface on whichthe Si layer easily grows in the Si film forming process described lateras compared to the surface of the SiO film.

(Residual Gas Removal)

After the seed layer is formed on the surface of the SiO film, the valve243 a of the first gas supply pipe 232 a is closed to stop the supply ofthe HCDS gas. At this time, while the APC valve 244 of the exhaust pipe231 is in an open state, the interior of the process chamber 201 isvacuum exhausted by the vacuum pump 246, and the HCDS gas remaining inthe process chamber 201 which does not react or remains aftercontributing to the formation of the seed layer is removed from theprocess chamber 201. Furthermore, at this time, the valves 243 e to 243g are in an open state, and the supply of the N₂ gas as an inert gasinto the process chamber 201 is maintained. The N₂ gas acts as a purgegas, and thus, it is possible to increase an effect of removing the HCDSgas remaining in the process chamber 201 which does not react or remainsafter contributing to the formation of the seed layer from the processchamber 201.

Moreover, at this time, the gas remaining in the process chamber 201 maynot be completely removed, and the interior of the process chamber 201may not be completely purged. When the gas remaining in the processchamber 201 is very small in amount, there is no adverse effectgenerated in the Si film forming process performed thereafter. At thistime, an amount of the N₂ gas supplied into the process chamber 201 neednot be a large amount, and, for example, approximately the same amountof the N₂ gas as the volume of the reaction tube 203 (the processchamber 201) may be supplied to perform the purge such that there is noadverse effect generated in the Si film forming process. As describedabove, as the interior of the process chamber 201 is not completelypurged, the purge time can be reduced, thereby improving the throughput.In addition, the consumption of the N₂ gas can also be suppressed to aminimal necessity.

As the chlorosilane-based precursor gas, an inorganic precursor gas suchas a tetrachlorosilane, i.e., silicon tetrachloride (SiCl₄,abbreviation: STC) gas, a trichlorosilane (SiHCl₃, abbreviation: TCS)gas, a dichlorosilane (SiH₂Cl₂, abbreviation: DCS) gas, and amonochlorosilane (SiH₃Cl, abbreviation: MCS) gas may be used, inaddition to the hexachlorodisilane (Si₂Cl₆, abbreviation: HCDS) gas. Asthe inert gas, a rare gas such as an Ar gas, a He gas, an Ne gas, and aXe gas may be used, in addition to the N₂ gas.

[Si Film Forming Process]

When the treatment process on the surface of the SiO film, i.e., theformation of the seed layer on the surface of the SiO film, iscompleted, the following two steps, i.e., Steps 1 and 2 are executed.

[Step 1]

(HCDS Gas Supply)

Here, by the same processing procedure as the treatment process, theHCDS gas as the second precursor is supplied to the wafer 200.

At this time, the APC valve 244 is appropriately adjusted to set theinternal pressure of the process chamber 201 to fall within a range of,for example, 1 to 13300 Pa, or more specifically, 20 to 1330 Pa. Asupply flow rate of the HCDS gas controlled by the MFC 241 a is set tofall within a range of, for example, 1 to 1000 sccm. A supply flow rateof the N₂ gas controlled by each of the MFCs 241 e to 241 g is set tofall within a range of, for example, 100 to 10000 sccm. A time ofsupplying the HCDS gas to the wafer 200, i.e., a gas supply time(irradiation time), is set to fall within a range of, for example, 1 to120 seconds, or more specifically, 1 to 60 seconds.

At this time, when the temperature of the wafer 200 is less than 250degrees C., very little of the HCDS is chemically adsorbed onto thewafer 200, and the practical film forming rate may not be obtained. Itis possible to solve this problem by setting the temperature of thewafer 200 to 250 degrees C. or more. Furthermore, by setting thetemperature of the wafer 200 to 300 degrees C. or more, or morespecifically 350 degrees C. or more, it is possible to more sufficientlyadsorb the HCDS onto the seed layer, and it is possible to obtain a moresufficient film forming rate. Further, when the temperature of the wafer200 exceeds 700 degrees C., the film thickness uniformity may easilydeteriorate making it difficult to control the film thickness uniformityas a CVD reaction is strengthened (a gaseous reaction becomes dominant).It is possible to suppress deterioration of the film thicknessuniformity by setting the temperature of the wafer 200 to 700 degrees C.or less and to control the film thickness uniformity. In particular, asurface reaction becomes dominant by setting the temperature of thewafer 200 to 650 degrees C. or less, or more specifically 600 degrees C.or less, the film thickness uniformity can be easily secured, and thus,it is easy to control the film thickness uniformity. Accordingly, whenthe temperature of the wafer 200 is set to fall within a range of, forexample, 250 to 700 degrees C., more specifically, 300 to 650 degreesC., or further more specifically, 350 to 600 degrees C., it is possibleto allow the process (formation of the first layer to be describedlater) in Step 1 to progress.

However, although the details will be described later, when thetemperature of the wafer 200 is less than 300 degrees C., it is hard fora modification reaction (modification reaction of the first layer) inStep 2 of the Si film forming process to be described later to progress.It is possible to facilitate the progress of the modification reactionin Step 2 by setting the temperature of the wafer 200 to 300 degrees C.or more. Further, the modification reaction in Step 2 becomes moreactive by setting the temperature of the wafer 200 to 350 degrees C. ormore. In addition, when the temperature of the wafer 200 exceeds 450degrees C., it is difficult to allow the modification reaction in Step 2to properly progress. That is, in order to allow the process in Step 2to efficiently and appropriately progress, the temperature of the wafer200 may be set in the range of, for example, 300 to 450 degrees C., ormore specifically, 350 to 450 degrees C.

In this way, appropriate temperature conditions differ between Steps 1and 2, and a temperature range suitable for allowing Step 2 to progressmay be included in a temperature range suitable for allowing Step 1 toprogress. Here, in order to improve the throughput of the Si filmforming process of performing the cycle including Steps 1 and 2 apredetermined number of times, the temperature of the wafer 200 in Steps1 and 2 may be set to have the same temperature conditions. That is, thetemperature conditions of the wafer 200 in Step 1 may be set to be equalto the temperature conditions of the wafer 200 in Step 2. Therefore, inStep 1, the temperature of the wafer 200 may be set to fall within arange of, for example, 300 to 450 degrees C., or more specifically, 350to 450 degrees C. Within this temperature range, it is possible to allowthe process (formation of the first layer) in Step 1 and the process(modification of the first layer) in Step 2 to efficiently andappropriately progress, respectively.

By supplying the HCDS gas under the above-described conditions, theSi-containing layer containing chlorine (Cl) having a thickness, forexample, of less than one atomic layer to several atomic layers isformed on the seed layer as the first layer. The first layer may be anadsorption layer of the HCDS gas, an Si layer containing Cl, or both.

Here, the Si layer containing Cl is a generic name including adiscontinuous layer as well as a continuous layer formed of Si andcontaining Cl, or an Si thin film containing Cl formed by laminating thediscontinuous layer and the continuous layer. Also, in some cases, acontinuous layer formed of Si and containing Cl may be referred to as anSi thin film containing Cl. In addition, Si forming the Si layercontaining Cl also includes Si, in which bonding to Cl is completelybroken, in addition to Si in which bonding to Cl is not completelybroken.

Moreover, the adsorption layer of the HCDS gas also includes achemisorption layer in which gas molecules of the HCDS gas arediscontinuous, in addition to a chemisorption layer in which the gasmolecules of the HCDS gas are continuous. That is, the adsorption layerof the HCDS gas includes a chemisorption layer having a thickness of onemolecular layer constituted by HCDS molecules or less than one molecularlayer. Further, HCDS (Si₂Cl₆) molecules constituting the adsorptionlayer of the HCDS gas also contains molecules in which bonding of Si andCl is partially broken (Si_(x)Cl_(y) molecules). That is, the adsorptionlayer of the HCDS gas includes a chemisorption layer in which Si₂Cl₆molecules and/or Si_(x)Cl_(y) molecules are continuous, or achemisorption layer in which Si₂Cl₆ molecules and/or Si_(x)Cl_(y)molecules are discontinuous.

Also, a layer having a thickness of less than one atomic layer refers toa discontinuously formed atomic layer, and a layer having a thickness ofone atomic layer refers to a continuously formed atomic layer. Inaddition, a layer having a thickness of less than one molecular layerrefers to a discontinuously formed molecular layer, and a layer having athickness of one molecular layer refers to a continuously formedmolecular layer.

Under a condition in which the HCDS gas is autolyzed (pyrolyzed), i.e.,under a condition in which a pyrolysis reaction of the HCDS gas occurs,the Si layer containing Cl is formed by depositing Si on the seed layer.Under a condition in which the HCDS gas is not autolyzed (pyrolyzed),i.e., under a condition in which a pyrolysis reaction of the HCDS gasdoes not occur, the adsorption layer of the HCDS gas is formed byadsorbing the HCDS gas onto t the seed layer. In addition, forming ofthe Si layer containing Cl on the seed layer can increase the filmforming rate rather than forming of the adsorption layer of the HCDS gason the seed layer.

When the thickness of the first layer formed on the seed layer exceedsseveral atomic layers, an effect of modification reaction in Step 2described later is not applied to the entire first layer. In addition, aminimum value of the thickness of the Si layer that can be formed on thewafer 200 is less than one atomic layer. Accordingly, the thickness ofthe first layer may be approximately less than one atomic layer toseveral atomic layers. In addition, as the thickness of the first layeris set to one atomic layer or less, i.e., one atomic layer or less thanone atomic layer, an effect of the modification reaction in Step 2described later can be relatively increased, and thus a time requiredfor the modification reaction in Step 2 can be reduced. A time requiredfor forming the first layer in Step 1 can also be reduced. As a result,a processing time per one cycle can be reduced, and a total processingtime can also be reduced. That is, the film forming rate can also beincreased. In addition, controllability of the film thickness uniformitycan also be increased by setting the thickness of the first layer to oneatomic layer or less.

Furthermore, the first layer is formed on the SiO film after thetreatment process, that is, on the continuously formed seed layer. As aresult, as will be described later, when the Si film is formed byperforming the cycle including Steps 1 and 2 a predetermined number oftimes, even if the film thickness thereof is set to fall within aso-called thin film range, for example, 5 Å to 100 Å, it is possible toform a film having no pinholes. Further, it is also possible to improvethe film thickness uniformity and improve the step coverage of the film.

Furthermore, since the first layer is formed on the SiO film after thetreatment process, that is, on the seed layer whose surface is Clterminated, when Steps 1 and 2 are set to one cycle and the cycle isperformed a predetermined number of times, the formation of the Si layerdescribed later is efficiently (without delay) started from an earlystage (from a stage in which a cycle was performed less number oftimes). That is, it is possible to shorten an incubation time of the Sifilm, thereby improving the total productivity of the Si film formingprocess. Furthermore, it is possible to suppress the total consumptionof the precursor gas, in particular, the consumption of a relativelyexpensive aminosilane-based precursor gas supplied in Step 2 describedbelow, thereby reducing the film forming costs.

Further, since the above-described seed layer is continuously formedthroughout the entire region on the surface of the wafer 200, it ispossible to uniformly align the incubation time of the Si film, that is,the timing of growth start of the Si layer to be described belowthroughout the entire region on the surface of the wafer 200. Thus, itis possible to suppress the influence of the timing offset of the growthstart on the film thickness, thereby improving the film thicknessuniformity of the Si film in the plane of the wafer 200.

(Residual Gas Removal)

After the first layer is formed, the interior of the process chamber 201is vacuum exhausted by the same procedure as the treatment process, andthe HCDS gas remaining in the process chamber 201 which does not reactor remains after contributing to the formation of the first layer isremoved from the process chamber 201.

Moreover, at this time, the gas remaining in the process chamber 201 maynot be completely removed, and the interior of the process chamber 201may not be completely purged. When the gas remaining in the processchamber 201 is very small in amount, there is no adverse effectgenerated in Step 2 performed thereafter. At this time, an amount of theN₂ gas supplied into the process chamber 201 need not be a large amount,and, for example, approximately the same amount of the N₂ gas as thevolume of the reaction tube 203 (the process chamber 201) may besupplied to perform the purge such that there is no adverse effectgenerated in Step 2. As described above, as the interior of the processchamber 201 is not completely purged, the purge time can be shortened,thereby improving the throughput. In addition, the consumption of the N₂gas can also be suppressed to a minimal necessity.

As the chlorosilane-based precursor gas, an inorganic precursor gas suchas a tetrachlorosilane, i.e., silicon tetrachloride (SiCl₄,abbreviation: STC) gas, a trichlorosilane (SiHCl₃, abbreviation: TCS)gas, a dichlorosilane (SiH₂Cl₂, abbreviation: DCS) gas, and amonochlorosilane (SiH₃Cl, abbreviation: MCS) gas may be used, inaddition to the hexachlorodisilane (Si₂Cl₆, abbreviation: HCDS) gas. Asthe inert gas, a rare gas such as an Ar gas, an He gas, an Ne gas, and aXe gas may be used, in addition to the N₂ gas.

[Step 2]

(SiH₃R Gas Supply)

After Step 1 is terminated and the residual gas in the process chamber201 is removed, the valve 243 b of the second gas supply pipe 232 b isopened to allow SiH₃R gas to flow, as a third precursor, into the secondgas supply pipe 232 b. A flow rate of the SiH₃R gas flowing into thesecond gas supply pipe 232 b is adjusted by the MFC 241 b. The flowrate-adjusted SiH₃R gas is supplied into the process chamber 201 throughthe gas supply holes 250 b of the second nozzle 249 b, and exhaustedfrom the exhaust pipe 231. At this time, the SiH₃R gas is supplied tothe wafer 200. At the same time, the valve 243 f is opened to allow theflow of N₂ gas as an inert gas into the second inert gas supply pipe 232f. A flow rate of the N₂ gas flowing in the second inert gas supply pipe232 f is adjusted by the MFC 241 f. The flow rate-adjusted N₂ gas issupplied into the process chamber 201 together with the SiH₃R gas, andexhausted through the exhaust pipe 231.

Furthermore, at this time, in order to prevent infiltration of the SiH₃Rgas into the first nozzle 249 a and the third nozzle 249 c, the valves243 e and 243 g are opened to allow the flow of N₂ gas into the firstinert gas supply pipe 232 e and the third inert gas supply pipe 232 g.The N₂ gas is supplied into the process chamber 201 through the firstgas supply pipe 232 a, the third gas supply pipe 232 c, the first nozzle249 a, and the third nozzle 249 c, and exhausted through the exhaustpipe 231.

At this time, the APC valve 244 is appropriately adjusted to set theinternal pressure of the process chamber 201 to fall within a range of,for example, 1 to 13300 Pa, or more specifically, 20 to 1330 Pa. Asupply flow rate of the SiH₃R gas controlled by the MFC 241 b is set tofall within a range of, for example, 1 to 1000 sccm. A supply flow rateof the N₂ gas controlled by each of the MFCs 241 e to 241 g is set tofall within a range of, for example, 100 to 10000 sccm. A time forsupplying the SiH₃R gas to the wafer 200, i.e., a gas supply time(irradiation time), is set to fall within a range of, for example, 1 to120 seconds, or more specifically, for example, 1 to 60 seconds.

In this case, similarly to Step 1, a temperature of the heater 207 isset such that a temperature of the wafer 200 falls within a range of,for example, 300 to 450 degrees C., more specifically, 300 to 450degrees C., or further more specifically, 350 to 450 degrees C.

When the temperature of the wafer 200 is less than 300 degrees C., theSiH₃R gas supplied to the wafer 200 is hardly autolyzed (pyrolyzed), anda ligand (R) containing an amino group is hardly separated from Si inthe SiH₃R gas. That is, the number of the ligands (R) that react withthe first layer (Si-containing layer containing Cl) formed in Step 1 islikely to become insufficient. As a result, a removal reaction of Clfrom the first layer becomes difficult.

The SiH₃R gas supplied to the wafer 200 is easily pyrolyzed by settingthe temperature of the wafer 200 to 300 degrees C. or more, and thus,the ligand (R) containing an amino group is easily separated from Si inthe SiH₃R gas. Moreover, as the separated ligand (R) reacts with thehalogen group (Cl) in the first layer, the removal reaction of Cl fromthe first layer easily occurs. Further, pyrolysis of the SiH₃R gassupplied to the wafer 200 becomes more active by setting the temperatureof the wafer 200 to 350 degrees or more, and thus, the number of theligands (R) separated from Si in the SiH₃R gas easily increases. Theremoval reaction of Cl from the first layer becomes more active by anincrease in the number of the ligands (R) which react with Cl in thefirst layer.

Moreover, thermal energy exceeding 450 degrees C. is necessary forbonding the ligand (R) containing the amino group, separated from Si inthe SiH₃R gas, to Si in the first layer (the Si-containing layer fromwhich Cl is removed), namely, Si (unpaired Si) which has a dangling bondby separating Cl from the first layer, or Si (Si which was not paired)which had dangling bond. Therefore, by setting the temperature of thewafer 200 to 450 degrees C. or less, the ligand (R) containing the aminogroup separated from Si in the SiH₃R gas can be prevented from beingbonded to an unpaired Si in the first layer or Si which was not paired.That is, by setting the temperature of the wafer 200 to 450 degrees C.or less, the ligand (R) containing the amino group can be prevented frombeing introduced into the first layer. As a result, an amount ofimpurities such as carbon (C) or nitrogen (N) can be considerablyreduced in the first layer after modification, namely, the second layerdescribed later.

Moreover, by setting the temperature of the wafer 200 to fall within thetemperature range of 300 to 450 degrees C., Si of the SiH₃R gas fromwhich the ligand (R) is separated, namely, Si (unpaired Si) having adangling bond included in the SiH₃R gas, is bonded to unpaired Si in thefirst layer or Si which was not paired, thereby facilitating theformation of Si—Si bonding.

Moreover, when the temperature of the wafer 200 exceeds 450 degrees C.,the ligand (R) containing the amino group separated from Si in the SiH₃Rgas can be easily bonded to unpaired Si in the first layer or Si whichwas not paired. That is, the ligand (R) containing the amino group canbe easily introduced into the first layer. Furthermore, an amount ofimpurities such as carbon (C) or nitrogen (N) can easily increase in thefirst layer after modification, namely, the second layer describedlater.

Therefore, the temperature of the wafer 200 may be set to fall within arange of, for example, 300 to 450 degrees C., or more specifically, forexample, 350 to 450 degrees C.

Under the above-described conditions, by supplying the SiH₃R gas to thewafer 200, the SiH₃R gas reacts with the first layer (the Si-containinglayer containing Cl) which is formed on the wafer 200 in Step 1. Thatis, by supplying the SiH₃R gas to the wafer 200 heated at theabove-described temperature, the ligand (R) containing the amino groupis separated from Si in the SiH₃R gas, and the separated ligand (R)reacts with Cl in the first layer to remove Cl from the first layer.Also, by heating the wafer 200 at the above-described temperature, theligand (R) containing the amino group separated from Si in the SiH₃R gasis prevented from being bonded to an unpaired Si in the first layer(Si-containing layer from which Cl is removed) or Si which was notpaired. Moreover, an unpaired Si of the SiH₃R gas from which the ligand(R) is separated is bonded to an unpaired Si in the first layer or Siwhich was not paired, thereby forming Si—Si bonding. Therefore, thefirst layer formed on the wafer 200 in Step 1 is changed (modified) intothe second layer which contains Si and is very small in content ofimpurities such as chlorine (Cl), carbon (C), or nitrogen (N). Inaddition, the second layer has a thickness of about less than one atomiclayer to several atomic layers. The second layer is an Si layer (Silayer) composed of Si which is very small in content of impurities suchas chlorine (Cl), carbon (C), or nitrogen (N). A crystalline structureof the Si layer has an amorphous state; thus, the Si layer may bereferred to as an amorphous Si layer (a-Si layer).

Moreover, when the Si layer is formed as the second layer, Cl containedin the first layer before modification mostly reacts with the ligand (R)containing the amino group included in the SiH₃R gas while themodification reaction of the first layer is performed by the SiH₃R gas,thereby generating, for example, a gaseous reaction byproduct such asamino salt, and the gaseous reaction byproduct is discharged from theprocess chamber 201 through the exhaust pipe 231. Accordingly, an amountof impurities such as Cl, C, or N contained in the modified first layer,namely, the second layer, can be reduced. Also, when the SiH₃R gas isused as an aminosilane-based precursor gas, since an amount of aminogroup contained in a composition formula thereof (an amount of aminogroup in one molecule) is small, that is, an amount of impurities suchas C or N contained in the composition is small, an amount of impuritiessuch as C or N contained in the modified first layer, namely, the secondlayer, can be easily reduced. In particular, an amount of N can begreatly reduced.

(Residual Gas Removal)

After the Si layer is formed, the valve 243 b of the second gas supplypipe 232 b is closed to stop the supply of the SiH₃R gas. At this time,while the APC valve 244 of the exhaust pipe 231 is in an open state, theinterior of the process chamber 201 is vacuum exhausted by the vacuumpump 246, and the SiH₃R gas remaining in the process chamber 201 whichdoes not react or remains after contributing to the formation of thesecond layer or reaction byproducts are removed from the process chamber201. Furthermore, at this time, the valves 243 e to 243 g are in an openstate, and the supply of the N₂ gas as an inert gas into the processchamber 201 is maintained. The N₂ gas acts as a purge gas, and thus, itis possible to increase an effect of removing the SiH₃R gas remaining inthe process chamber 201 which does not react or remains aftercontributing to the formation of the second layer or the reactionbyproducts from the process chamber 201.

Moreover, at this time, the gas remaining in the process chamber 201 maynot be completely removed, and the interior of the process chamber 201may not be completely purged. When the gas remaining in the processchamber 201 is very small in amount, there is no adverse effectgenerated in Step 1 performed thereafter. At this time, an amount of theN₂ gas supplied into the process chamber 201 need not be a large amount,and, for example, approximately the same amount of N₂ gas as the volumeof the reaction tube 203 (the process chamber 201) may be supplied toperform the purge such that there is no adverse effect generated in Step1. As described above, as the interior of the process chamber 201 is notcompletely purged, the purge time can be reduced, thereby improving thethroughput. In addition, the consumption of the N₂ gas can also besuppressed to a minimal necessity.

As an aminosilane-based precursor, organic precursors such asdiaminosilane (SiH₂RR′), triaminosilane (SiHRR′R″), and tetraaminosilane(SiRR′R″R′″)) may be used in addition to monoaminosilane (SiH₃R). Here,each of R, R′, R″, and R′″ represents a ligand, and represents an aminogroup in which one or two hydrocarbon groups containing one or more Catoms are coordinated in one N atom herein (one or both of H of theamino group represented by NH₂ is substituted with a hydrocarbon groupcontaining one or more C atoms). If two hydrocarbon groups constitutinga part of the amino group are coordinated in one N, the two hydrocarbongroups may be the same hydrocarbon group, or may be differenthydrocarbon groups. Further, the hydrocarbon group may include anunsaturated bonding such as a double bond or a triple bond. Further, theamino group of each of R, R′, R″, and R′″ may be the same amino group,or may be different amino groups. Further, the amino group may have acyclic structure. For example, as SiH₂RR′, it is possible to usebis(diethylamino)silane (SiH₂[N(C₂H₅)₂]₂, abbreviation: BDEAS),bis(tertiary-butylamino)silane (SiH₂[NH(C₄H₉)]₂, abbreviation: BTBAS),bis(diethylpiperidino)silane (SiH₂[NC₅H₈(C₂H₅)₂]₂, abbreviated: BDEPS)and the like. Further, as SiHRR′R″, it is possible to use, for example,tris(diethylamino)silane (SiH[N(C₂H₅)₂]₃, abbreviation: 3DEAS),tris(dimethylamino)silane (SiH[N(CH₃)₂]₃, abbreviation: 3DMAS) and thelike. Further, as SiRR′R″R′″, it is possible to use, for example,tetrakis(diethylamino) silane (Si[N(C₂H₅)₂]₄, abbreviation: 4DEAS),tetrakis(dimethylamino)silane (Si[N(CH₃)₂]₄, abbreviation: 4DMAS) andthe like.

Furthermore, as the aminosilane-based precursor, it is possible to usean organic precursor in which the number of ligands containing an aminogroup in the composition formula is two or less, and equal to or lessthan the number of ligands containing a halogen group in the compositionformula of the chlorosilane-based precursor.

In the case of using, for example, HCDS(Si₂Cl₆), STC(SiCl₄),TCS(SiHCl₃), and DCS(SiH₂Cl₂) in which the number of ligands (Cl)containing a halogen group in the composition formula is equal to orgreater than 2 as a chlorosilane-based precursor, it is possible to usediaminosilane (SiH₂RR′) in which the number of ligands (R) containing anamino group in the composition formula is 2 as an aminosilane-basedprecursor, in addition to monoaminosilane (SiH₃R) in which the number ofligands (R) containing an amino group in the composition formula is 1.Further, in the case of using MCS(SiH₃Cl) in which the number of ligands(Cl) containing a halogen group in the composition formula is 1 as achlorosilane-based precursor, it is possible to use monoaminosilane(SiH₃R) in which the number of ligands (R) containing an amino group inthe composition formula is 1 as an aminosilane-based precursor.

Further, the number of ligands (R) containing an amino group in thecomposition formula of the aminosilane-based precursor may be smallerthan the number of ligands (Cl) containing a halogen group in thecomposition formula of the chlorosilane-based precursor. Therefore, inthe case of using DCS in which the number of ligands (Cl) containing ahalogen group in the composition formula is 2 as a chlorosilane-basedprecursor, it is preferable to use monoaminosilane in which the numberof ligands (R) containing an amino group in the composition formula is 1as an aminosilane-based precursor, rather than diaminosilane in whichthe number of ligands (R) containing an amino group in the compositionformula is 2.

Further, the number of ligands (R) containing an amino group in thecomposition formula of the aminosilane-based precursor may be 1.Therefore, as the aminosilane-based precursor, it is possible to usemonoaminosilane rather than diaminosilane. In this case, in order forthe number of ligands (R) containing an amino group in the compositionformula of the aminosilane-based precursor to be set to be smaller thanthe number of ligands (Cl) containing a halogen group in the compositionformula of the chlorosilane-based precursor, it is possible to use HCDS,STC, TCS, and DCS in which the number of ligands (Cl) containing ahalogen group in the composition formula is 2 or more as achlorosilane-based precursor.

Therefore, an amount of Cl contained in the first layer (theSi-containing layer containing Cl) before modification is larger than anamount of the ligand (R) including the amino group contained in theSiH₃R gas supplied to the first layer (the Si-containing layer includingCl) in Step 2. In this case, the ligand (R) containing the amino groupcontained in the SiH₃R gas mostly reacts with Cl contained in the firstlayer before modification, and generate, for example, a gaseous reactionbyproduct such as amino salt during the modification reaction of thefirst layer. The gaseous reaction byproduct is discharged from theinside of the process chamber 201 through the exhaust pipe 231. That is,the ligand (R) containing the amino group contained in the SiH₃R gas ismostly discharged from the process chamber 201 to thereby be removedwithout being introduced into the modified first layer, namely, thesecond layer. As a result, the first layer after the modification,namely, the second layer, may be changed (modified) into a silicon layerin which an amount of impurities, such as C or N, is very small.

The inert gas may include a rare gas such as an Ar gas, an He gas, an Negas, a Xe gas, or the like, in addition to the N₂ gas.

(Performing Predetermined Number of Times)

By setting the above-described Steps 1 and 2 to one cycle and performingthe cycle one or more times (a predetermined number of times), it ispossible to form an Si film composed of Si with a very small amount ofimpurities such as Cl, C, and N, as a film containing a predeterminedelement, on a surface of a treated SiO film, i.e., on the seed layer.Furthermore, the seed layer may be considered as part of the base filmof the Si layer, or may be considered as a part of the Si film. Thecrystalline structure of the Si film has an amorphous state (amorphous),and the Si film may also be referred to as an amorphous silicon film(a-Si film). Furthermore, the above-described cycle may be repeatedmultiple times. That is, it is possible to set a thickness of the Silayer formed per cycle to be smaller than a desired thickness and torepeat the above-described cycle multiple times until the desired filmthickness is obtained.

Furthermore, in the case of performing the cycle multiple times, at eachstep at least after the second cycle, the expression “a predeterminedgas is supplied to the wafer 200” may mean that “a predetermined gas issupplied to a surface formed on the wafer 200, i.e., on the uppermostsurface of the wafer 200 as a laminated body.” Also, the expression “apredetermined layer is formed on the wafer 200” may mean that “apredetermined layer is formed on a layer formed on the wafer 200, i.e.,on the uppermost surface of the wafer 200 as a laminated body.” Theabove-described matters are similar to respective modified examples andother embodiments as will be described later.

(Purge and Return to Atmospheric Pressure)

When the film forming process of forming the Si film having apredetermined film thickness is performed, the valves 243 e to 243 g areopened to supply the N₂ gas as an inert gas into the process chamber 201from each of the first inert gas supply pipe 232 e and the second inertgas supply pipe 232 f, and exhaust the N₂ gas from the exhaust pipe 231.The N₂ gas acts as the purge gas, whereby the interior of the processchamber 201 is purged with the inert gas, and the gas remaining in theprocess chamber 201 or the reaction byproducts are removed from theprocess chamber 201 (purge). Thereafter, an atmosphere in the processchamber 201 is substituted with the inert gas (inert gas substitution),and the internal pressure of the process chamber 201 returns to normalpressure (return to atmospheric pressure).

(Boat Unloading and Wafer Discharging)

Thereafter, the seal cap 219 is lowered by the boat elevator 115 to openthe lower end of the reaction tube 203, and the processed wafer 200supported on the boat 217 is unloaded outside of the reaction tube 203through the lower end of the reaction tube 203 (boat unloading).Thereafter, the processed wafer 200 is discharged from the boat 217(wafer discharging).

(3) Effects According to the Embodiment

According to the embodiment, one or a plurality of effects are providedas described below.

(a) According to the film forming sequence of the embodiment, the Sifilm is formed on the SiO film after the treatment process, that is, onthe continuously formed seed layer. As a result, when the Si film isformed by performing the cycle including Steps 1 and 2 a predeterminednumber of times, even if the film thickness thereof is set to fallwithin a so-called thin film range, for example, 5 Å to 100 Å, or morespecifically, 20 Å to 100 Å, it is possible to form an Si film having nopinholes with satisfactory film thickness uniformity. Further, it ispossible to improve the step coverage of the Si film.

(b) According to the film forming sequence of the embodiment, since theSi film is formed on the SiO film after the treatment process, that is,on the seed layer on which the surface is Cl terminated, when the cycleincluding Steps 1 and 2 is performed a predetermined number of times,the formation of the Si layer is started from an early stage withoutdelay. That is, it is possible to shorten an incubation time of the Sifilm, thereby improving the total productivity of the Si film formingprocess. Furthermore, it is possible to suppress the total consumptionof the precursor gas, thereby reducing the film forming costs.

(c) According to the film forming sequence of the embodiment, since theabove-described seed layer is continuously formed throughout the entireregion in the surface of the wafer 200, it is possible to make theincubation time of the Si film uniform, that is, the timing of growthstart of the Si layer throughout the entire region in the surface of thewafer 200. Thus, it is possible to suppress the influence on the filmthickness due to the timing offset of the growth start, therebyimproving the film thickness uniformity of the Si film in the plane ofthe wafer 200.

(d) According to the film forming sequence of the embodiment, when theinternal pressure of the process chamber 201 in the treatment process isset to be higher than the internal pressure of the process chamber 201during supply of the HCDS gas, or the supply flow rate of the HCDS gasin the treatment process is set to be greater than the supply flow rateof the HCDS gas in the Si film forming process, it is possible toincrease a forming rate of a seed layer on the surface of the SiO film,thereby improving the total productivity in the film forming process.Also, the seed layer is easily formed to a continuous layer, and as aresult, it is also possible to improve the film thickness uniformity ofthe Si film in the plane of the wafer 200 or the step coverage.

(e) According to the film forming sequence of the embodiment, whenperforming the cycle including Steps 1 and 2 a predetermined number oftimes, a temperature of the wafer 200 is set such that the ligand (R)containing an amino group is separated from Si in the SiH₃R gas, theseparated ligand reacts with Cl in the first layer to remove Cl from thefirst layer, the separated ligand is prevented from being bonded to Siin the first layer, and Si obtained by separating the ligand in theSiH₃R gas is bonded to Si in the first layer. Specifically, thetemperature of the wafer 200 is set to fall within a range of 300 to 450degrees C., or more specifically a range of 350 to 450 degrees C.

Thus, it is possible to modify the first layer formed in Step 1 into asecond layer (Si layer) having very small content of impurities such asCl, C, and N. Moreover, by performing the cycle including Steps 1 and 2a predetermined number of times, it is possible to form a high-qualitySi film having a very small content of impurities such as Cl, C, and Nat a low temperature range. Furthermore, as a result of intensivestudies, the inventors found that when performing the cycle includingSteps 1 and 2 a a predetermined number of times, if a temperature of thewafer 200 was set to a temperature exceeding 450 degrees C., C of aconcentration of 5% or more was observed in the Si film. In contrast, itwas confirmed that it is possible to form a high-quality Si film havinga very small content of impurities by setting a temperature of the wafer200 to a temperature in the range of 300 to 450 degrees C., or morespecifically, 350 to 450 degrees C.

Furthermore, the Si film formed by this film forming method becomes adense film having a high wet-etching resistance to HF or the like, andis suitably used as an etching mask film or the like when etching thebase SiO film or the like, for example, using HF. However, in this case,since the Si film is not an insulating film such as an SiO film or anSiN film, the Si film needs to be removed after, for example, use as anetching mask film.

(f) According to the film forming sequence of the embodiment, in Step 2,as an aminosilane-based precursor gas, the SiH₃R gas with few aminogroups included in the composition formula (per molecule) is used.Specifically, a precursor gas containing a single amino group in thecomposition formula (per molecule) is used. Thus, by using a precursorgas in which an amount of C and N containing in the composition is smallas an aminosilane-based precursor gas, it becomes easy to reduce anamount of impurities such as C and N containing in the second layer tobe formed in Step 2, and thus, in particular, it is possible tosignificantly reduce the amount of N.

(g) According to the film forming sequence of the embodiment, it ispossible to form an Si film even at a low temperature range by the useof two precursors (silane source) of a chlorosilane-based precursor andan aminosilane-based precursor. Furthermore, according to theexperiments of the inventors, when using only a chlorosilane-basedprecursor member, it was difficult to deposit Si on the wafer at a filmforming rate that meets the production efficiency in the temperaturerange of 500 degrees C. or less. Furthermore, when using only anaminosilane-based precursor member, the deposition of Si onto the waferwas not confirmed in a temperature range of 500 degrees C. or less.However, according to the method of the embodiment, it is possible toform a high-quality Si film at a film forming rate that meets theproduction efficiency even in a low-temperature range of 500 degrees C.or less, for example, in a temperature range of 300 to 450 degrees C.

In addition, when the film forming temperature is set to alow-temperature, kinetic energy of the molecules is typically reduced,and it becomes difficult for a reaction or desorption of chlorinecontained in the chlorosilane-based precursor or amine contained in theaminosilane-based precursor to occur, and thus these ligands remain onthe wafer surface. Moreover, due to steric hindrance of the residualligands, the adsorption of Si onto the wafer surface is inhibited, Sidensity decreases, and degradation of the film occurs. However, evenunder a condition in which it is hard for such reaction or desorption toprogress, the residual ligands can be desorbed by allowing two silanesources, that is, a chlorosilane-based precursor and anaminosilane-based precursor to properly react with each other. Moreover,the steric hindrance is eliminated by desorption of the residualligands, whereby it is possible to adsorb Si to an open site, therebyincreasing the Si density. In this manner, it is possible to form a filmhaving a high Si density even in a low-temperature range of 500 degreesC. or more, for example, in a temperature range of 300 to 450 degrees C.

(h) According to the embodiment, it is possible to form a high-qualitySi film by a thermal reaction (thermochemical reaction) under anon-plasma atmosphere (without using plasma) at a low temperature range.Further, since it is possible to form an Si film without using plasma,the embodiment may be applied to a process having a probability ofplasma damage.

(i) According to the embodiment, since it is possible to allow thereaction to appropriately progress under a condition in which thesurface reaction progress is dominant by using an alternate supplyingmethod of alternately supplying the chlorosilane-based precursor and theaminosilane-based precursor to the wafer 200, it is possible to improvethe step coverage of the Si film. Further, it is possible to improve thecontrollability of the film thickness of the Si film.

(4) Modified Example

In the above-described film forming sequence shown in FIGS. 4 and 5A, anexample, in which after a surface of the SiO film formed on the surfaceof the wafer 200 is treated, an Si film having a predetermined thicknessis formed on a surface of a treated SiO film, i.e., on the seed layer byperforming the cycle including Steps 1 and 2 a predetermined number oftimes, was described. However, the film forming sequence according tothe embodiment may be varied as described later without being limitedthereto.

Modified Example 1

For example, as shown in FIG. 6, after performing the seed layer formingstep of the film forming sequence shown in FIGS. 4 and 5A, and the Silayer forming step by performing the cycle including Steps 1 and 2 apredetermined number of times (n times), a step of supplying aninorganic silane-based precursor gas (for example, SiH₄ gas) to thewafer 200 may be performed to form a CVD-Si layer by a chemical vapordeposition (CVD) method. Thus, it is possible to form an Si filmconstituted by the Si layer and the CVD-Si layer laminated in this orderon a surface of a treated SiO film, i.e., on the seed layer.

In order to form a CVD-Si layer, the valve 243 c of the third gas supplypipe 232 c is opened to allow the flow of an SiH₄ gas as a fourthprecursor into the third gas supply pipe 232 c. A flow rate of the SiH₄gas flowing into the third gas supply pipe 232 c is adjusted by the MFC241 c. The flow rate-adjusted SiH₄ gas is supplied into the processchamber 201 through the gas supply holes 250 c of the third nozzle 249c, and exhausted from the exhaust pipe 231. At this time, the SiH₄ gasis supplied to the wafer 200. At the same time, the valve 243 g isopened to allow the flow of an inert gas such as N₂ gas into the inertgas supply pipe 232 g. A flow rate of the N₂ gas flowing in the inertgas supply pipe 232 g is adjusted by the MFC 241 g. The flowrate-adjusted N₂ gas is supplied into the process chamber 201 togetherwith the SiH₄ gas, and exhausted through the exhaust pipe 231.

Furthermore, at this time, in order to prevent infiltration of the SiH₄gas into the first nozzle 249 a and the second nozzle 249 b, the valves243 e and 243 f are opened to allow the flow of the N₂ gas into thefirst inert gas supply pipe 232 e and the second inert gas supply pipe232 f. The N₂ gas is supplied into the process chamber 201 through thefirst gas supply pipe 232 a, the second gas supply pipe 232 b, the firstnozzle 249 a, and the second nozzle 249 b, and exhausted through theexhaust pipe 231.

At this time, the APC valve 244 is appropriately adjusted to set theinternal pressure of the process chamber 201 to fall within a range of,for example, 1 to 1000 Pa. A supply flow rate of the SiH₄ gas controlledby the MFC 241 c is set to fall within a range of, for example, 1 to1000 sccm. A supply flow rate of the N₂ gas controlled by each of theMFCs 241 e to 241 g is set to fall within a range of, for example, 100to 10000 sccm. A temperature of the heater 207 is set such that atemperature of the wafer 200 falls within a range of, for example, 350to 700 degrees. A CVD-Si layer having a predetermined thickness isformed on the Si layer by supplying the SiH₄ gas to the wafer 200 underthe above-described conditions.

After the CVD-Si layer having a predetermined thickness is formed, thevalve 243 c of the third gas supply pipe 232 c is closed to stop thesupply of the SiH₄ gas. At this time, while the APC valve 244 of theexhaust pipe 231 is in an open state, the interior of the processchamber 201 is vacuum exhausted by the vacuum pump 246, and the SiH₄ gasremaining in the process chamber 201 which does not react or remainsafter contributing to the formation of the CVD-Si layer is removed fromthe process chamber 201. Furthermore, at this time, the valves 243 e to243 g are in an open state, and the supply of the N₂ gas as an inert gasinto the process chamber 201 is maintained. The N₂ gas acts as a purgegas, and thus, it is possible to increase an effect of removing the SiH₄gas remaining in the process chamber 201 which does not react or remainsafter contributing to the formation of the CVD-Si layer from the processchamber 201.

Thus, an Si film is formed by sequentially laminating the Si layer andthe CVD-Si layer on a surface of a treated SiO film, i.e., on the seedlayer. Furthermore, by using an inorganic silane-based precursor gascontaining no Cl, C, and N as a precursor gas, the CVD-Si layer may havevery small amount of impurities such as Cl, C, and N. That is, the Sifilm becomes a film having a very small amount of impurities such as Cl,C, and N.

According to this modified example, since the seed layer and the Silayer are previously formed on the surface of the SiO film formed on thesurface of the wafer 200, it is possible to improve a film thicknessuniformity of the Si film in a plane of the wafer 200. If the Si film isdirectly formed on the surface of the SiO film by a CVD method, Si growsin an island shape on the surface of the SiO film at an initial stage ofthe Si film growth, resulting in a decrease of a film thicknessuniformity of the Si film in a plane of the wafer 200. Also, in somecases, an incubation time of the Si film may increase, productivity maydecrease, and the film forming cost may increase. In contrast, accordingto this modified example, by previously forming a seed layer and an Silayer on the surface of the SiO film, it is possible to avoid the growthof Si in an island shape at the initial stage of forming of the CVD-Silayer, thereby improving a film thickness uniformity of the Si film in aplane of the wafer 200. Further, it is also possible to shorten theincubation time of the Si film, thereby improving the productivity andreducing the film forming costs. Further, it is also possible to improvethe film forming rate of the Si film by using a CVD method.

Furthermore, as an inorganic silane-based precursor gas, a polysilanegas (Si_(n)H_(2n+2) (n>2)) gas such as a disilane (Si₂H₆) gas and atrisilane (Si₃H₈) gas may be used, in addition to the monosilane (SiH₄)gas. The polysilane gas may also be referred to as an inorganicsilane-based precursor gas containing no Cl. As an inert gas, a rare gassuch as an Ar gas, an He gas, an Ne gas, and a Xe gas may be used inaddition to the N₂ gas.

Modified Example 2

For example, as shown in FIG. 7, after performing the seed layer formingstep of the film forming sequence shown in FIGS. 4 and 5A, and the Silayer forming step by performing the cycle including Steps 1 and 2 apredetermined number of times (n times), a CVD-Si layer may be formed bya chemical vapor deposition (CVD) method using an inorganicsilane-basedprecursor gas (for example, SiH₄ gas), and then, an Si film may beformed by performing the cycle including Steps 1 and 2 of the filmforming sequence shown in FIGS. 4 and 5A a predetermined number of times(n times). Thus, it is possible to form an Si film constituted by the Silayer, the CVD-Si layer, and the Si layer laminated in this order on asurface of a treated SiO film, i.e., on the seed layer.

Modified Example 3

Furthermore, for example, as shown in FIG. 8, after performing the seedlayer forming step of the film forming sequence shown in FIGS. 4 and 5Aand the Si layer forming step by performing the cycle including Steps 1and 2 a predetermined number of times (n times), a silicon carbonitridelayer (SiCN layer) may be formed by performing a cycle including Step 3of supplying a chlorosilane-based precursor gas (for example, HCDS gas)to the wafer 200, and Step 4 of supplying an aminosilane-based precursorgas (for example, 3DMAS gas) to the wafer 200 a predetermined number oftimes (n times). Thus, it is possible to form a layer constituted by theSi layer and the SiCN layer laminated in this order on a surface of atreated SiO film, i.e., on the seed layer. That is, a laminated filmconstituted by laminating the Si film and the silicon carbonitride film(SiCN film) is formed. Hereinafter, Steps 3 and 4 will be described.

[Step 3]

(HCDS Gas Supply)

Step 3 of supplying the HCDS gas to the wafer 200 is performed by thesame procedures and processing conditions as Step 1 of the film formingsequence shown in FIGS. 4 and 5A. However, the temperature of the wafer200 is set to fall within a range of, for example, 250 to 700 degreesC., more specifically, 300 to 650 degrees C., or further morespecifically, 350 to 600 degrees C. Thus, an Si-containing layercontaining Cl which has a thickness of, for example, less than oneatomic layer to several atomic layers is formed on the Si layer formedon the wafer 200.

(Residual Gas Removal)

After the Si-containing layer containing Cl is formed, and the HCDS gasremaining in the process chamber 201 which does not react or remainsafter contributing to the formation of the Si-containing layer orreaction byproducts are removed from the process chamber 201, by thesame procedures and processing conditions as Step 1. At this time, inthe same manner as Step 1, the gas remaining in the process chamber 201may not be completely removed, and the interior of the process chamber201 may not be completely purged.

[Step 4]

(3DMAS Gas Supply)

After Step 3 is terminated to remove the residual gas in the processchamber 201, the valve 243 d of the fourth gas supply pipe 232 d isopened to allow the flow of a 3DMAS gas as a fifth precursor into thefourth gas supply pipe 232 d. A flow rate of the 3DMAS gas flowing intothe fourth gas supply pipe 232 d is adjusted by the MFC 241 d. The flowrate-adjusted 3DMAS gas flows through the third gas supply pipe 232 c.Then, the flow rate-adjusted 3DMAS gas is supplied into the processchamber 201 through the gas supply holes 250 c of the third nozzle 249c, and exhausted from the exhaust pipe 231. At this time, the 3DMAS gasis supplied to the wafer 200. At the same time, the valve 243 g isopened to allow the flow of an inert gas such as the N₂ gas into theinert gas supply pipe 232 g. A flow rate of the N₂ gas flowing in theinert gas supply pipe 232 g is adjusted by the MFC 241 g. The flowrate-adjusted N₂ gas is supplied into the process chamber 201 togetherwith the 3DMAS gas, and exhausted through the exhaust pipe 231.

Furthermore, at this time, in order to prevent infiltration of the 3DMASgas into the first nozzle 249 a and the second nozzle 249 b, the valves243 e and 243 f are opened to allow the flow of the N₂ gas into thefirst inert gas supply pipe 232 e and the second inert gas supply pipe232 f. The N₂ gas is supplied into the process chamber 201 through thefirst gas supply pipe 232 a, the second gas supply pipe 232 b, the firstnozzle 249 a, and the second nozzle 249 b, and exhausted through theexhaust pipe 231.

At this time, the APC valve 244 is appropriately adjusted to set theinternal pressure of the process chamber 201 to fall within a range of,for example, 1 to 13300 Pa, more specifically, 20 to 1330 Pa. A supplyflow rate of the 3DMAS gas controlled by the MFC 241 d is set to fallwithin a range of, for example, 1 to 1000 sccm. A supply flow rate ofthe N₂ gas controlled by each of the MFCs 241 e to 241 g is set to fallwithin a range of, for example, 100 to 10000 sccm. A time of supplyingthe 3DMAS gas to the wafer 200, i.e., a gas supply time (irradiationtime), is set to fall within a range of, for example, 1 to 120 seconds,or more specifically, 1 to 60 seconds. A temperature of the wafer 200 isset to fall within a range of, for example, 250 to 700 degrees C., morespecifically, 300 to 650 degrees C., or further more specifically, 350to 600 degrees C.

By supplying the 3DMAS gas to the wafer 200 under the above-describedconditions, the Si-containing layer containing Cl formed on the Si layeron the wafer 200 in Step 1 reacts with the 3DMAS gas. Thus, theSi-containing layer containing Cl is modified into a layer containingSi, C, and N, i.e., an SiCN layer. The SiCN layer becomes a layercontaining Si, C, and N with a thickness, for example, of less than oneatomic layer to several atomic layers. Furthermore, the SiCN layerbecomes a layer in which a ratio of an Si component and a ratio of a Ccomponent are relatively large, i.e., a layer being Si-rich and C-rich.

(Residual Gas Removal)

After the SiCN layer is formed, the valve 243 d of the fourth gas supplypipe 232 d is closed to stop the supply of the 3DMAS gas. At this time,while the APC valve 244 of the exhaust pipe 231 is in an open state, theinterior of the process chamber 201 is vacuum exhausted by the vacuumpump 246, and the 3DMAS gas remaining in the process chamber 201 whichdoes not react or remains after contributing to the formation of theSiCN layer is removed from the process chamber 201. Furthermore, at thistime, the valves 243 e to 243 g are in an open state, and the supply ofthe N₂ gas as an inert gas into the process chamber 201 is maintained.The N₂ gas acts as a purge gas, and thus, it is possible to increase aneffect of removing the HCDS gas remaining in the process chamber 201which does not react or remains after contributing to the formation ofthe SiCN layer from the process chamber 201. At this time, in the samemanner as Step 3, the gas remaining in the process chamber 201 may notbe completely removed, and the interior of the process chamber 201 maynot be completely purged.

(Performing Predetermined Number of Times)

By setting the above-described Steps 3 and 4 to one cycle and performingthe cycle one or more times (a predetermined number of times), it ispossible to form an SiCN layer having a predetermined thickness.Moreover, it is possible to form a layer constituted by lamination ofthe Si layer and the SiCN layer. In other words, a laminated filmconstituted by laminating the Si film and the SiCN film on a surface ofa treated SiO film, that is, on the seed layer is formed.

Furthermore, as a chlorosilane-based precursor gas supplied in Step 3,an STC gas, a TCS gas, a DCS gas, an MCS gas and the like may be used inaddition to the HCDS gas. Further, as an aminosilane-based precursor gassupplied in Step 4, a BDEAS gas, a BTBAS gas, a BDEPS gas, a 3DEAS gas,a 4DEAS gas, a 4DMAS gas and the like may be used in addition to the3DMAS gas. As an inert gas, a rare gas such as Ar gas, He gas, Ne gas,and Xe gas may be used in addition to the N₂ gas.

Other Embodiments of the Present Disclosure

While some embodiments of the present disclosure have been described indetail, the present disclosure is not limited to the above-describedembodiments but can be variously modified without departing from thescope thereof.

For example, in the above-described embodiments, an example in which anSiO film serving as a semiconductor oxide film is formed on the surfaceof the wafer 200, as the insulating film has been described, but thepresent disclosure is not limited to such embodiments. For example, asthe insulating film, a semiconductor nitride film such as a siliconnitride film (Si₃N₄ film, hereinafter also referred to as an SiN film),a semiconductor oxynitride film such as a silicon oxynitride film (SiONfilm), a semiconductor oxycarbide film such as a silicon oxycarbide film(SiOC film), a semiconductor oxycarbonitride film such as siliconoxycarbonitride film (SiOCN film) may be formed on the surface of thewafer 200. Further, for example, a metal oxide film such as an aluminumoxide film (Al₂O₃ film, hereinafter, also referred to as an AlO film), atitanium oxide film (TiO₂ film, hereinafter, also referred to as a TiOfilm), a hafnium oxide film (HfO₂ film, hereinafter, also referred to asan HfO film) a zirconium oxide film (ZrO₂ film, hereinafter, alsoreferred to as a ZrO film), a ruthenium oxide film (Ru₂O film,hereinafter, also referred to as a RuO film), and a tungsten oxide film(WO₃ film, hereinafter, also referred to as a WO film), and a metalnitride film such as a titanium nitride film (TiN film) may be formed onthe surface of the wafer 200. In addition, for example, a metaloxynitride film such as a titanium oxynitride film (TiON film), a metaloxycarbide film such as a titanium oxycarbide film (TiOC film), a metaloxycarbonitride film such as a titanium oxycarbonitride film (TiOCNfilm) and the like may be formed on the surface of the wafer 200.Furthermore, the oxide film (or nitride film, oxynitride film,oxycarbide film, oxycarbonitride film) herein includes a CVD oxide filmformed, for example, by a CVD method, an oxide film formed by performinga predetermined process, such as, for example, thermal oxidation processor plasma oxidation process to intentionally oxide the surface of thewafer 200, and a natural oxide film naturally formed on the surface ofthe wafer 200 by being exposed to air during transfer.

Furthermore, as a result of intensive studies, the inventors found thatin particular, if the insulating film is a film containing O,especially, the SiO film, the above-described problems may occur. Thatis, a film thickness uniformity of the Si film formed on the insulatingfilm in a plane of the wafer 200 is easily reduced, the step coverageeasily decreases, or the incubation time easily increases. In otherwords, it has been found that if the insulating film formed on thesurface of the wafer 200 is a film containing O, especially, the SiOfilm, the effect of the above-described treatment process can beparticularly remarkably achieved.

Further, for example, in the above-described embodiments, while anexample of using a chlorosilane-based precursor as the first precursorand the second precursor, respectively has been described, asilane-based precursor having halogen-based ligands other than a chlorogroup may be used instead of the chlorosilane-based precursor. Forexample, a fluorosilane-based precursor may be used instead of thechlorosilane-based precursor. Here, the fluorosilane-based precursor isa silane-based precursor having a fluoro group as a halogen group, and aprecursor containing at least silicon (Si) and fluorine (F). In otherwords, the fluorosilane-based precursor herein may also be referred toas a kind of halide. As a fluorosilane-based precursor gas, it ispossible to use, for example, a silicon fluoride gas such as atetrafluorosilane, i.e., silicontetrafluoride (SiF₄) gas or ahexafluorodisilane (Si₂F₆) gas. In this case, the seed layer is a layercontaining F as a halogen group, and more specifically, a layercontaining F as a halogen group and Si as a predetermined element.Further, the first layer is a layer containing Si and F, that is, anSi-containing layer containing F. However, a chlorosilane-basedprecursor may be used as a silane-based precursor having a halogengroup, in view of the vapor pressure of the precursor or the vaporpressure of the reaction product produced in Step 2.

Further, for example, in the above-described embodiments, while anexample of using the HCDS gas as the first precursor and the secondprecursor, respectively, that is, an example in which the firstprecursor and the second precursor consist of the same substances hasbeen described, the present disclosure is not limited to suchembodiments. For example, the present disclosure can be suitably appliedeven in the case of using the HCDS gas as the first precursor and theDCS gas as the second precursor, or in the case of using the DCS gas asthe first precursor and the HCDS gas as the second precursor. Further,the present disclosure can be suitably applied, for example, in the caseof using a chlorosilane-based precursor as the first precursor and afluorosilane-based precursor as the second precursor, or in the case ofusing a fluorosilane-based precursor as the first precursor and achlorosilane-based precursor as the second precursor. That is, thepresent disclosure can be suitably applied even if the first precursorand the second precursor consist of different substances.

Further, for example, in the above-described embodiment, while anexample of performing the treatment process and the Si film formingprocess in the same process chamber 201 has been described, the presentdisclosure is not limited to such embodiments. That is, the treatmentprocess and the Si film forming process may be independently performedin respective process chambers. In this case, the processing conditionsin the treatment process and the processing conditions in the Si filmforming process may be varied in a wider range than the above-describedembodiments. For example, it is possible to more efficiently perform theformation of the seed layer by setting temperature conditions(temperature of the wafer 200) in the Si film forming process to behigher than temperature conditions (temperature of the wafer 200) in thetreatment process.

Further, for example, in the above-described embodiment, while anexample of forming a seed layer on the surface of the SiO film formed onthe surface of the wafer 200 in the treatment process has beendescribed, the present disclosure is not limited to such embodiments.For example, pre-processing (Cl terminating) of the surface of the SiOfilm formed on the surface of the wafer 200 may be performed in thetreatment process by supplying a hydrogen chloride gas (HCl gas), achlorine gas (Cl₂ gas) or the like to the wafer 200 with the SiO filmformed on the surface. That is, in the treatment process, Cl terminatedsurface of the SiO film may be formed rather than forming a seed layeron the surface of the SiO film. In this case, it is possible to obtainthe effect of the same tendency as the above-described embodiment bysetting a temperature of the wafer 200 in the treatment process to arelatively high temperature, for example, to a temperature higher than atemperature of the wafer 200 in the Si film forming process.

Further, for example, in the above-described embodiment, as shown inFIG. 5A, while an example of supplying a chlorosilane-based precursor tothe wafer 200 in the treatment process, supplying a chlorosilane-basedprecursor to the wafer 200 in the Si film forming process, and thensupplying an aminosilane-based precursor has been described, in thiscase, a residual gas removal step in the treatment process may not beprovided. That is, as shown in FIG. 5B, an HCDS gas supply step in thetreatment process and Step 1 of the first cycle in the Si film formingprocess may be continuously performed rather than between the residualgas removal steps. In this case, since the residual gas removal step maynot be provided, it is possible to improve the throughput of the filmforming process. However, by performing the residual gas removal step inthe treatment process, it is possible to separate Step 1 of thetreatment process and the Si film forming process, whereby it ispossible to independently set the processing conditions in the treatmentprocess (flow rate of HCDS gas, internal pressure of the process chamber201 and the like), thereby facilitating the control of the forming rate,thickness, or composition of the seed layer. Furthermore, when changinga point of view, the film forming sequence shown in FIG. 5B can beconsidered that a gas supply time of the HCDS gas in Step 1 of the firstcycle of the Si film forming process is set to be longer than a gassupply time of the HCDS gas in Step 1 after the second cycle.

Further, for example, in the above-described embodiment, while anexample of supplying a chlorosilane-based precursor to the wafer 200 inthe Si film forming process and then supplying an aminosilane-basedprecursor has been described, the supply order of these precursors maybe reversed. That is, the chlorosilane-based precursor may be suppliedafter supplying the aminosilane-based precursor. That is, one of thechlorosilane-based precursor and the aminosilane-based precursor may besupplied, and then the other thereof may be supplied. Thus, by changingthe order of supplying the precursor, it is also possible to vary thequality of the thin film to be formed. Further, in the case of supplyingthe aminosilane-based precursor and then supplying thechlorosilane-based precursor, since the above-described modificationprocess is performed on the seed layer during supply of theaminosilane-based precursor at the first cycle, it is possible to reducethe content of impurities such as Cl, C, and N containing in the seedlayer.

Further, for example, in the above-described embodiment, while anexample of using monoaminosilane (SiH₃R) as a third precursor(aminosilane-based precursor) in the Si film forming process has beendescribed, the present disclosure is not limited to such examples. Thatis, as a third precursor, organic precursors, such as for example,diaminosilane (SiH₂RR′), triaminosilane (SiHRR′R″), tetraaminosilane(SiRR′R″R′″) and the like may be used. That is, as a third precursor, aprecursor containing two, three, or four amino groups in the compositionformula (in one molecule) may be used. Thus, even if a precursorcontaining a plurality of amino groups in the composition formula (inone molecule) is used as a third precursor, it is possible to form an Sifilm with a small content of impurities such as C and N at a lowtemperature range.

However, the smaller the number of amino groups included in thecomposition formula of the third precursor is, that is, the smaller theamount of C or N contained in the composition is, the easier to reducethe amount of impurities such as C or N contained in the first layer,and the easier to form an Si film with a very small content ofimpurities. That is, when SiH₃R, SiH₂RR′ or SiHRR′R″ is used as a thirdprecursor rather than SiRR′R″R′″, it becomes easy to reduce the amountof impurities contained in the Si film. Also, when SiH₃R or SiH₂RR′ isused as a third precursor rather than SiHRR′R″, it becomes easy toreduce the amount of impurities contained in the Si film. Furthermore,when SiH₃R is used as a third precursor rather than SiH2RR′, it becomeseasy to reduce the amount of impurities contained in the Si film.

Furthermore, in the above-described embodiment, while an example offorming an Si film on a surface of a treated SiO film by performing thecycle including the chlorosilane-based precursor gas supply step and theaminosilane-based precursor gas supply step a predetermined number oftimes has been described, the present disclosure is not limited to suchexamples.

For example, the present disclosure can also be applied to the followingcases: a case of forming an SiN film on a surface of a treated SiO filmby performing a cycle including a chlorosilane-based precursor gassupply step and a nitrogen-containing gas supply step a predeterminednumber of times; a case of forming an SiO film on a surface of a treatedSiO film by performing a cycle including a chlorosilane-based precursorgas supply step and an oxygen-containing gas supply step a predeterminednumber of times; a case of forming an SiO film on a surface of a treatedSiO film by performing a cycle including a chlorosilane-based precursorgas supply step and a step of supplying a gas obtained by adding ahydrogen-containing gas to an oxygen-containing gas a predeterminednumber of times; or a case of forming an SiO film on a surface of atreated SiO film by performing a cycle including a chlorosilane-basedprecursor gas supply step, a nitrogen-containing gas supply step, and anoxygen-containing gas supply step a predetermined number of times.

Furthermore, for example, the present disclosure can also be applied tothe following cases: a case of forming an SiCN film on a surface of atreated SiO film by performing a cycle including a chlorosilane-basedprecursor gas supply step, a carbon-containing gas supply step, and anitrogen-containing gas supply step a predetermined number of times; ora case of forming an SiOCN film on a surface of a treated SiO film byperforming a cycle including a chlorosilane-based precursor gas supplystep, a carbon-containing gas supply step, a nitrogen-containing gassupply step, and an oxygen-containing gas supply step a predeterminednumber of times.

In addition, for example, the present disclosure can also be applied tothe following cases: a case of forming an SiCN film on a surface of atreated SiO film by performing a cycle including a chlorosilane-basedprecursor gas supply step and an amine-based gas supply step apredetermined number of times; or a case of forming an SiOCN film on asurface of a treated SiO film by performing a cycle including achlorosilane-based precursor gas supply step, an amine-based gas supplystep, and an oxygen-containing gas supply step a predetermined number oftimes.

Also, for example, the present disclosure can also be applied to thefollowing cases: a case of forming an SiBN film on a surface of atreated SiO film by performing a cycle including a chlorosilane-basedprecursor gas supply step, a boron-containing gas supply step, and anitrogen-containing gas supply step a predetermined number of times; ora case of forming an SiBCN film on a surface of a treated SiO film byperforming a cycle including a chlorosilane-based precursor gas supplystep, a carbon-containing gas supply step, a boron-containing gas supplystep, and a nitrogen-containing gas supply step a predetermined numberof times.

Furthermore, for example, the present disclosure can also be applied tothe following cases:

a case of forming an SiBCN film having a borazine ring structure on asurface of a treated SiO film by performing a cycle including achlorosilane-based precursor gas supply step and an organicborazine-based gas supply step a predetermined number of times; or acase of forming an SiBCN film or an SiBN film having a borazine ringstructure on a surface of a treated SiO film by performing a cycleincluding a chlorosilane-based precursor gas supply step, an organicborazine-based gas supply step, and a nitrogen-containing gas supplystep a predetermined number of times.

In these cases, as a nitrogen-containing gas, it is possible to use, forexample, an ammonia (NH₃) gas, a diazene (N₂H₂) gas, a hydrazine (N₂H₄)gas, an N₃H₈ gas, a gas containing these compounds or the like.

As an oxygen-containing gas, it is possible to use, for example, anoxygen (O₂) gas, a nitrous oxide (N₂O) gas, a nitrogen monoxide (NO)gas, a nitrogen dioxide (NO₂) gas, an ozone (O₃) gas, a water vapor(H₂O) gas, a carbon monoxide (CO) gas, a carbon dioxide (CO₂) gas or thelike. As a gas obtained by adding a hydrogen-containing gas (reducinggas) to the oxygen-containing gas, it is possible to use, for example,O₂ gas+H₂ gas, O₃ gas+H₂ gas or the like.

As a carbon-containing gas, it is possible to use, for example, ahydrocarbon-based gas such as an acetylene (C₂H₂) gas, a propylene(C₃H₆) gas, and an ethylene (C₂H₄) gas, that is, a carbon-containing gascontaining no nitrogen.

As an amine-based gas, it is possible to use an ethylamine-based gasobtained by vaporizing triethylamine ((C₂H₅)₃N, abbreviation: TEA), adiethylamine ((C₂H₅)₂NH, abbreviation: DEA), a monoethylamine (C₂H₅NH₂,abbreviation: MEA) and the like, a methylamine-based gas obtained byvaporizing trimethylamine ((CH₃)₃N, abbreviation: TMA), a dimethylamine((CH₃)₂NH, abbreviation: DMA), a monomethylamine (CH₃NH₂, abbreviation:MMA) and the like, a propylamine-based gas obtained by vaporizingtripropylamine ((C₃H₇)₃N, abbreviation: TPA), a dipropylamine((C₃H₇)₂NH, abbreviation: DPA), a monopropylamine (C₃H₇NH₂,abbreviation: MPA) and the like, an isopropyl amine-based gas obtainedby vaporizing triisopropylamine ([(CH₃)₂CH]₃N, abbreviation: TIPA),diisopropylamine ([(CH₃)₂CH]₂NH, abbreviation: DIPA), monoisopropylamine((CH₃)₂CHNH₂, abbreviation: MIPA) and the like, a butylamine-based gasobtained by vaporizing tributylamine (C₄H₉)₃N, abbreviation: TBA),dibutylamine ((C₄H₉)₂NH, abbreviation: DBA), monobutylamine (C₄H₉NH₂,abbreviation: MBA) and the like, an isobutylamine-based gas obtained byvaporizing triisobutylamine ([(CH₃)₂CHCH₂]₃N, abbreviation: TIBA),diisobutylamine ([(CH₃)₂CHCH₂]₂NH, abbreviation: DIBA),monoisobutylamine ((CH₃)₂CHCH₂NH₂, abbreviation: MIBA) and the like.That is, as the amine-based gas, it is possible to use at least one ofthe gases containing, for example, (C₂H₅)_(x)NH_(3-x),(CH₃)_(x)NH_(3-x), (C₃H₇)_(x)NH_(3-x), [(CH₃)₂CH]_(x)NH_(3-x),(C₄H₉)_(x)NH_(3-x), and [CH₃)₂CHCH₂]_(x)NH_(3-x) (x is an integer from 1to 3 in the chemical formula).

Furthermore, it is also possible to use an organic hydrazine-based gasinstead of the amine-based gas. As the organic hydrazine-based gas, itis possible to use, for example, a methyl hydrazine-based gas obtainedby vaporizing monomethylhydrazine ((CH₃)HN₂H₂, abbreviation: MMH),dimethylhydrazine ((CH₃)₂N₂H₂, abbreviation: DMH), trimethylhydrazine((CH₃)₂N₂ (CH₃)H, abbreviation; TMH) and the like, or anethylhydrazine-based gas obtained by vaporizing ethylhydrazine((C₂H₅)HN₂H₂, abbreviation: EH) and the like.

As the boron-containing gas, it is possible to use, for example, ahalogenated boron-based gas such as a boron trichloride (BCl₃) gas andboron trifluoride gas (BF₃) gas, an inorganic borane-based gas such asdiborane (B₂H₆) gas, and an organic borazine-based gas. As the organicborazine-based gas, it is possible to use, for example, an organicborazine compound gas such as an n, n′, n″-trimethylborazine(abbreviation: TMB) gas.

As the chlorosilane-based precursor gas, it is possible to use the samegas in the above-described embodiments. Furthermore, the processingconditions at this time may be set to the same processing conditions asthe above-described embodiment. However, the temperature of the wafer200 may be set to fall within a range of, for example, 250 to 700degrees C., more specifically, 300 to 650 degrees C., or further morespecifically, 350 to 600 degrees C.

Thus, it is possible to appropriately apply the present disclosure to asubstrate processing process using a chlorosilane-based precursor gasand a nitrogen-containing gas, a substrate processing process using achlorosilane-based precursor gas and an oxygen-containing gas, asubstrate processing process using a chlorosilane-based precursor gasand a hydrogen-containing gas, a substrate processing process using achlorosilane-based precursor gas and a carbon-containing gas, asubstrate processing process using a chlorosilane-based precursor gasand a carbon-containing or nitrogen-containing gas, a substrateprocessing process using a chlorosilane-based precursor gas and aboron-containing gas or the like. That is, the present disclosure can beapplied to the overall substrate processing process using at least oneof a nitrogen-containing gas (nitriding gas), an oxygen-containing gas(oxidizing gas), a hydrogen-containing gas (reducing gas), acarbon-containing gas (hydrocarbon-based gas), a carbon andnitrogen-containing gas (amine-based gas, organic hydrazine gas), and aboron-containing gas (halogenated boron-based gas, inorganicborazine-based gas, organic borazine-based gas), as a third precursor.That is, the present disclosure can be applied to the overall substratetreatment process of forming a film on the SiO film using achlorosilane-based precursor gas.

Further, it is possible to provide a device forming technique havingexcellent workability by using an Si film, an Si-based insulating film,or a B-based insulating film formed by the method of the embodiment asan etching stopper. Furthermore, an Si film formed by the method of theembodiment can be appropriately applied to various applications such asa floating gate electrode or a control gate electrode of a semiconductormemory device, channel silicon, a gate electrode of a transistor, acapacitor electrode of a DRAM, an STI liner, and a solar cell. Further,by the use of an Si-based insulating film or a B-based insulating filmformed by the method of the embodiment as a side wall spacer, it ispossible to provide a device forming technique with small leakagecurrent and having excellent workability.

According to the above-described embodiments or modified examples, it ispossible to form an Si film, an Si-based insulating film, and a B-basedinsulating film of an ideal stoichiometric ratio without using plasmaeven at a low temperature range. Further, since it is possible to forman Si film, an Si-based insulating film, and a B-based insulating filmwithout using plasma, the embodiment may be applied to a process havingprobability of plasma damage, for example, an SADP film of DPT.

Furthermore, in the above-described embodiment, an example of forming anSi film containing silicon, which is a semiconductor element, as a thinfilm containing a predetermined element has been described, but thepresent disclosure can be applied to a case of forming a metal-basedthin film containing a metal element such as titanium (Ti), zirconium(Zr), hafnium (Hf), tantalum (Ta), aluminum (Al), molybdenum (Mo) or thelike.

In this case, it is possible to form a film by the same film formingsequence as in the above-described embodiments, by using a precursor(second precursor) containing a metal element and a halogen groupinstead of the chlorosilane-based precursor in the above-describedembodiment, and by using a precursor (third precursor) containing ametal element and a halogen group instead of the aminosilane-basedmaterial. As the second precursor, it is possible to use, for example, aprecursor containing a metal element and a chloro group, or a precursorcontaining a metal element and a fluoro group.

In this case, the following processes are performed: a process ofperforming treatment on a surface of an insulating film by supplying afirst precursor containing a metal element and a halogen group to thewafer 200 with an insulating film formed on the surface; and a processof forming a metal-based thin film containing a metal element on asurface of a treated insulating film by performing a cycle including astep of supplying a second precursor containing the metal element andthe halogen group to the wafer 200, and a step of supplying a thirdprecursor to the wafer 200 a predetermined number of times.

For example, when a Ti film that is a Ti-based thin film composed of Tiis formed as a metal-based thin film, as a first precursor and a secondprecursor, it is possible to use a precursor containing Ti and a chlorogroup such as titanium tetrachloride (TiCl₄), or a precursor containingTi and a fluoro group such as titanium tetrafluoride (TiF₄). As thethird precursor, it is possible to use a precursor containing Ti and anamino group such as tetrakis(ethylmethylamino)titanium(Ti[N(C₂H₅)(CH₃)]₄, abbreviation: TEMAT),tetrakis(dimethylamino)titanium (Ti[N(CH₃)₂]₄, abbreviation: TDMAT), ortetrakis(diethylamido)titanium (Ti[N(C₂H₅)₂]₄, abbreviation: TDEAT).Further, as the third precursor, it is also possible to use a precursorcontaining Ti and an amino group in which the number of ligandscontaining an amino group in the composition formula is 2 or less, andequal to or less than the number of ligands containing a halogen groupin the composition formula of the second precursor. Furthermore, as thethird precursor, a precursor containing a single amino group in thecomposition formula may be used. Furthermore, the processing conditionsat this time may be the same processing conditions as theabove-described embodiment.

When a Zr film that is a Zr-based thin film composed of Zr is formed asa metal-based thin film, as a first precursor and a second precursor, itis possible to use a precursor containing Zr and a chloro group such aszirconium tetrachloride (ZrCl₄), or a precursor containing Zr and afluoro group such as zirconium tetrafluoride (ZrF₄). As the thirdprecursor, it is possible to use a precursor containing Zr and an aminogroup such as tetrakis(ethylmethylamino)zirconium (Zr[N(C₂H₅)(CH₃)]₄,abbreviation: TEMAZ), tetrakis(dimethylamino)zirconium (Zr[N(CH₃)₂]₄,abbreviation: TDMAZ), or tetrakis(diethylamino)zirconium (Zr[N(C₂H₅)₂]₄,abbreviation: TDEAZ). Further, as the third precursor, it is alsopossible to use a precursor containing Zr and an amino group in whichthe number of ligands containing an amino group in the compositionformula is 2 or less, and equal to or less than the number of ligandscontaining a halogen group in the composition formula of the secondprecursor. Furthermore, as the third precursor a precursor containing asingle amino group in the composition formula may be used. Furthermore,the processing conditions at this time may be the same processingconditions as the above-described embodiment.

Also, when an Hf film that is an Hf-based thin film composed of Hf isformed as a metal-based thin film, as a first precursor and a secondprecursor, it is possible to use a precursor containing Hf and a chlorogroup such as hafnium tetrachloride (HfCl₄), or a precursor containingHf and a fluoro group such as hafnium tetrafluoride (HfF₄). As the thirdprecursor, it is possible to use a precursor containing Hf and an aminogroup, such as, tetrakis(ethylmethylamino)hafnium (Hf[N(C₂H₅)(CH₃)]₄,abbreviation: TEMAH), tetrakis(dimethylamino)hafnium (Hf[N(CH₃)₂]₄,abbreviation: TDMAH), or tetrakis(diethylamido)hafnium (Hf[N(C₂H₅)₂]₄,abbreviation: TDEAH). Further, as the third precursor, it is alsopossible to use a precursor containing Hf and an amino group in whichthe number of ligands containing an amino group in the compositionformula is 2 or less, and equal to or less than the number of ligandscontaining a halogen group in the composition formula of the secondprecursor. Furthermore, as the third precursor, a precursor containing asingle amino group in the composition formula may be used. Furthermore,the processing conditions at this time may be set to the same processingconditions as the above-described embodiment.

Furthermore, even in these cases, it is possible to form variousmetal-based thin films such as a metal-based nitride film, a metal-basedoxide film, a metal-based oxynitride film, and a metal-basedoxycarbonitride film, by using a gas including at least one of anitrogen-containing gas, an oxygen-containing gas, a hydrogen-containinggas, a carbon-containing gas, a carbon and nitrogen-containing gas, anda boron-containing gas as a third precursor.

Thus, the present disclosure can be also applied not only to asemiconductor-based thin film but to film formation of a metal-basedthin film, and the effects of the same tendency as the above-describedembodiment can be obtained even in this case.

Furthermore, each of process recipes (programs in which processingprocedures and processing conditions are written) used for formingvarious thin films may be individually prepared (prepared in the pluralnumber), depending the contents of the substrate processing (a film typeof a thin film to be formed, a composition ratio, a film quality, a filmthickness or the like). Moreover, when starting the substrateprocessing, an appropriate process recipe may be appropriately selectedfrom the plurality of process recipes, depending on the contents of thesubstrate processing. Specifically, the plurality of process recipesindividually prepared depending on the contents of the substrateprocessing may be stored (installed) in the storage device 121 cprovided in the substrate processing apparatus in advance, through atelecommunication line or a recording medium (external storage device123) storing the process recipe. Moreover, when starting the substrateprocessing, the CPU 121 a provided in the substrate processing apparatusappropriately select the proper process recipe from the plurality ofprocess recipes stored in the storage device 121 c, depending on thecontents of the substrate processing. With such a configuration, it ispossible to form thin films of various film types, composition ratios,film qualities, and film thicknesses in one substrate processingapparatus for general purpose with good reproducibility. Further, it ispossible to reduce the operation load of an operator (input load suchprocessing procedures and processing conditions), thereby quicklystarting the substrate processing, while avoiding erroneous operation.

However, the above-described process recipe is not limited to the caseof being newly created but may be prepared, for example, by changing theexisting process recipes previously installed in the substrateprocessing apparatus. When the process recipe is changed, the changedprocess recipe may be installed in the substrate processing apparatusvia an electric communication line or a recording medium storing theprocess recipe. Further, the existing process recipe previouslyinstalled in the substrate processing apparatus may be directly changedby operating the input/output device 122 provided in the existingsubstrate processing apparatus.

Furthermore, in the above-described embodiment, an example of forming athin film using a batch type substrate processing apparatus configuredto process a plurality of substrates at a time has been described, butthe present disclosure is not limited thereto but can also beappropriately applied to a case of forming a thin film using asingle-wafer type substrate processing apparatus in which one or severalsubstrates are processed at a time. Furthermore, in the above-describedembodiment, an example of forming a thin film using a substrateprocessing apparatus having a hot wall type processing furnace has beendescribed, but the present disclosure is not limited thereto but canalso be appropriately applied to a case of forming a thin film using asubstrate processing apparatus having a cold wall type processingfurnace.

Furthermore, the above-described embodiments, modified and the like maybe used appropriately combined and used.

EXAMPLES

As an example, the treatment process was performed on the wafers with aninsulating film (SiO film) formed on a surface by performing the filmforming sequence shown in FIGS. 4 and 5A using the above-describedsubstrate processing apparatus. Thereafter, a process of forming an Sifilm on the surface of the treated SiO film i.e., on a seed layer wasperformed. The HCDS gas was used as the first precursor and the secondprecursor, and the SiH₃R gas was used as the third precursor. A wafertemperature at the time of forming the film was set to 450 degrees C. Inaddition, a pressure in the process chamber in the treatment process wasset to be higher than a pressure in the process chamber during supply ofthe HCDS gas in the Si film forming process. Other processing conditionswere set to a predetermined value within the processing condition rangedescribed in the above-described example. Furthermore, as a comparativeexample, an Si film was directly formed on an SiO film by performing acycle including an HCDS gas supply process and an SiH₃R gas supplyprocess a predetermined number of times without performing the treatmentprocessing on the wafer with the SiO film formed on the surface. Thecomparative example is different from the example only in that thetreatment process is not performed on the SiO film as a base of theformation of the Si film, and other processing procedures and processingconditions were set to be the same as in the example. Moreover, the filmforming rates of the Si film according to the example and the Si filmaccording to the comparative example were measured, respectively, andthe results are shown in FIG. 9.

FIG. 9 is a graph showing measurement results of the film forming rateof the Si film according to the example and the comparative example. Ahorizontal axis of FIG. 9 represents the number of times of execution ofthe cycle [times], and the vertical axis represents a film thickness [Å]of the Si film. Furthermore, the mark “Δ” of FIG. 9 represents athickness of an Si film according to the example, and the mark “▪”represents a film thickness of the Si film according to the comparativeexample.

As shown in FIG. 9, it was confirmed that the forming of the Si filmaccording to the example is started from an early stage (from the firstcycle) than the forming of the Si film according to the comparativeexample. Further, it was confirmed that in the Si film according to thecomparative example, the growth of the Si film was not initiated untilthe cycle was repeated 50 times, and the growth is initiated finallyfrom around when the number of times of execution of the cycle exceeds50 times. That is, it was confirmed that it is possible to significantlyreduce the incubation time during film formation by performing thetreatment processing on the wafer with the SiO film formed on thesurface before starting the Si film forming process, thereby increasingthe productivity and reducing the film forming costs.

Aspects of Present Disclosure

Hereinafter, some aspects of the present disclosure will be additionallystated.

(Supplementary Note 1)

According to an aspect of the present disclosure, there is provided amethod of manufacturing a semiconductor device, including: treating asurface of an insulating film formed on a substrate by supplying a firstprecursor containing a predetermined element and a halogen group to thesubstrate; and forming a thin film containing the predetermined elementon the treated surface of the insulating film by performing a cycle apredetermined number of times, the cycle including supplying a secondprecursor containing the predetermined element and a halogen group tothe substrate and supplying a third precursor to the substrate.

(Supplementary Note 2)

In some embodiments, a supply time of the first precursor is set to belonger than a gas supply time of the second precursor per the cycle.

(Supplementary Note 3)

In some embodiments, the supply time of the first precursor is set tofall within a range of 120 to 1200 second.

(Supplementary Note 4)

In some embodiments, the supply time of the first precursor is set tofall within a range of 300 to 900 second.

(Supplementary Note 5)

In some embodiments, the supply time of the first precursor is set tofall within a range of 600 to 900 second.

(Supplementary Note 6)

In some embodiments, a flow rate of first precursor is set to be greaterthan a flow rate of the second precursor.

(Supplementary Note 7)

In some embodiments, a pressure of a space where the substrate existswhen supplying the first precursor is set to be higher than a pressureof a space where the substrate exists when supplying the secondprecursor.

(Supplementary Note 8)

In some embodiments, the first precursor and the second precursorconsists of the same substance.

(Supplementary Note 9)

In some embodiments, in the act of treating the surface of theinsulating film, a seed layer is formed on the surface of the insulatingfilm.

(Supplementary Note 10)

In some embodiments, in the act of treating the surface of theinsulating film, a seed layer containing the halogen group is formed onthe surface of the insulating film.

(Supplementary Note 11)

In some embodiments, in the act of treating the surface of theinsulating film, a seed layer containing the halogen group and thepredetermined element is formed on the surface of the insulating film.

(Supplementary Note 12)

In some embodiments, a thickness of the seed layer is 0.5 to 2 Å.

(Supplementary Note 13)

In some embodiments, the third precursor contains the predeterminedelement and an amino group.

(Supplementary Note 14)

In some embodiments, the third precursor contains the predeterminedelement and an amino group, and the thin film is composed of thepredetermined element.

(Supplementary Note 15)

In some embodiments, the third precursor contains one amino group in acomposition formula thereof (in one molecule).

(Supplementary Note 16)

In some embodiments, the third precursor includes at least one of anitriding gas (nitrogen-containing gas), an oxidizing gas(oxygen-containing gas), a reducing gas (hydrogen-containing gas), ahydrocarbon-based gas (carbon-containing gas), a carbon andnitrogen-containing gas (amine-based gas, and organic hydrazine gas),and a boron-containing gas (halogenated boron-based gas, inorganicborazine-based gas, and organic borazine-based gas).

(Supplementary Note 17)

In some embodiments, the halogen group includes a chloro group or afluoro group.

(Supplementary Note 18)

In some embodiments, the halogen group includes chlorine or fluorine.

(Supplementary Note 19)

In some embodiments, the predetermined element includes a semiconductorelement or a metal element.

(Supplementary Note 20)

In some embodiments, the predetermined element includes silicon.

(Supplementary Note 21)

In some embodiments, the predetermined element includes silicon, and thethin film includes a silicon film.

(Supplementary Note 22)

In some embodiments, the insulating film includes at least one of anoxide film, a nitride film, and an oxynitride film.

(Supplementary Note 23)

According to another aspect of the present disclosure, there is provideda method of processing a substrate, including: treating a surface of aninsulating film formed on a substrate by supplying a first precursorcontaining a predetermined element and a halogen group to the substrate;and forming a thin film containing the predetermined element on thetreated surface of the insulating film by performing a cycle apredetermined number of times, the cycle including supplying a secondprecursor containing the predetermined element and a halogen group tothe substrate and supplying a third precursor to the substrate.

(Supplementary Note 24)

According to still another aspect of the present disclosure, there isprovided a substrate processing apparatus, including: a process chamberconfigured to accommodate a substrate; a first precursor supply systemconfigured to supply a first precursor containing a predeterminedelement and a halogen group into the process chamber; a second precursorsupply system configured to supply a second precursor containing thepredetermined element and a halogen group into the process chamber; athird precursor supply system configured to supply a third precursorinto the process chamber; and a control unit configured to control thefirst precursor supply system, the second precursor supply system, andthe third precursor supply system so as to perform a process ofsupplying the first precursor to the substrate with an insulating filmformed thereon in the process chamber to treat a surface of theinsulating film, and a process of forming a thin film containing thepredetermined element on the treated surface of the insulating film byperforming a cycle a predetermined number of times, the cycle includingsupplying the second precursor to the substrate in the process chamberand supplying the third precursor to the substrate in the processchamber.

(Supplementary Note 25)

According to still another embodiment of the present disclosure, thereis provided a program that causes a computer to perform a process of:supplying a first precursor containing a predetermined element and ahalogen to a substrate with an insulating film formed thereon in aprocess chamber of a substrate processing apparatus to treat a surfaceof the insulating film; and forming a thin film containing thepredetermined element on the treated surface of the insulating film byperforming a cycle a predetermined number of times, the cycle includingsupplying a second precursor containing the predetermined element and ahalogen group to the substrate in the process chamber and supplying athird precursor to the substrate.

(Supplementary Note 26)

According to still another embodiment of the present disclosure, thereis provided a non-transitory computer-readable recording medium storinga program that causes a computer to perform a process of: supplying afirst precursor containing a predetermined element and a halogen to asubstrate with an insulating film formed thereon in a process chamber ofa substrate processing apparatus to treat a surface of the insulatingfilm; and forming a thin film containing the predetermined element onthe treated surface of the insulating film by performing a cycle apredetermined number of times, the cycle including supplying a secondprecursor containing the predetermined element and a halogen group tothe substrate in the process chamber and supplying a third precursor tothe substrate.

According to the present disclosure in some embodiments, it is possibleto improve step coverage of a thin film, and productivity of the filmforming process, when forming the thin film on a substrate with aninsulating film formed on a surface.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the disclosures. Indeed, the novel methods and apparatusesdescribed herein may be embodied in a variety of other forms;furthermore, various omissions, substitutions and changes in the form ofthe embodiments described herein may be made without departing from thespirit of the disclosures. The accompanying claims and their equivalentsare intended to cover such forms or modifications as would fall withinthe scope and spirit of the disclosures.

What is claimed is:
 1. A method of manufacturing a semiconductor device,comprising: treating a surface of an insulating film formed on asubstrate by supplying a first gas containing a halogen group to thesubstrate; and forming a thin film containing a predetermined element onthe treated surface of the insulating film by performing a cycle apredetermined number of times, the cycle comprising: supplying a secondgas containing the predetermined element and a halogen group to thesubstrate; and supplying a third gas to the substrate, wherein in theact of treating the surface of the insulating film, the surface of theinsulating film is terminated by the halogen group.
 2. The method ofclaim 1, wherein a temperature of the substrate when treating thesurface of the insulating film is set higher than a temperature of thesubstrate when forming the thin film.
 3. The method of claim 1, whereinthe first gas and the second gas comprise the same substance.
 4. Themethod of claim 1, wherein the first gas comprises at least one selectedfrom a group consisting of a hydrogen chloride gas and a chlorine gas.5. The method of claim 1, wherein the first gas further contains thepredetermined element.
 6. The method of claim 1, wherein the third gascontains the predetermined element and an amino group.
 7. The method ofclaim 1, wherein the thin film is composed of the predetermined element.8. The method of claim 1, wherein the third gas contains one amino groupin one molecule.
 9. The method of claim 1, wherein the third gascomprises at least one selected from a group consisting of anitrogen-containing gas, an oxygen-containing gas, a hydrogen-containinggas, a carbon-containing gas, a carbon- and nitrogen-containing gas, anda boron-containing gas.
 10. The method of claim 1, wherein the halogengroup comprises a chloro group or a fluoro group.
 11. The method ofclaim 1, wherein the insulating film comprises at least one selectedfrom a group consisting of an oxide film, a nitride film, and anoxynitride film.
 12. A method of manufacturing a semiconductor device,comprising: treating a surface of an insulating film formed on asubstrate by supplying a first gas containing a halogen group to thesubstrate; and forming a thin film containing a predetermined element onthe treated surface of the insulating film by performing a cycle apredetermined number of times, the cycle comprising: supplying a secondgas containing the predetermined element and a halogen group to thesubstrate; and supplying a third gas to the substrate, wherein in theact of treating the surface of the insulating film, a seed layercontaining the halogen group is formed on the surface of the insulatingfilm, and wherein a thickness of the seed layer is 0.5 to 2 Å.
 13. Amethod of manufacturing a semiconductor device, comprising: treating asurface of an insulating film formed on a substrate by supplying a firstgas containing a halogen group to the substrate; and forming a thin filmcontaining a predetermined element on the treated surface of theinsulating film by performing a cycle a predetermined number of times,the cycle comprising: supplying a second gas containing thepredetermined element and a halogen group to the substrate; andsupplying a third gas to the substrate, wherein the first gas and thesecond gas comprise different substances.
 14. A non-transitorycomputer-readable recording medium storing a program that causes acomputer to perform a process of: treating a surface of an insulatingfilm formed on a substrate by supplying a first gas containing a halogengroup to the substrate; and forming a thin film containing apredetermined element on the treated surface of the insulating film byperforming a cycle a predetermined number of times, the cyclecomprising: supplying a second gas containing the predetermined elementand a halogen group to the substrate; and supplying a third gas to thesubstrate, wherein in the process of treating the surface of theinsulating film, the surface of the insulating film is terminated by thehalogen group.